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GPPA1THH-A 06/02
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Nickel Metal Hydride
Technical
Hand Book
Table of Contents
1 Introduction
1.1 Overview
1.1.1 Chemistry - The Early Days
1.1.2 Well Established Product Series
1.2 NiMH Chemistry
1.2.1 Principle
1.2.2 Positive Electrode Chemistry
1.2.3 Negative Electrode Chemistry
1.2.4 Overall Reaction
1.2.5 Cell Pressure Management - Charge Reserve
1.2.6 Minimizing Damage During Deep Discharge - Discharge Reserve
1.3 Cell Construction
2 Performance Characteristics
2.1 Charging Characteristics
2.1.1 Overview
2.1.2 Charging Efficiency
2.2 Discharge Characteristics
2.2.1 Overview
2.2.2 Discharge Voltage
2.2.3 Discharge Capacity
2.2.4 Polarity Reversal During Over-discharge
2.3 Storage Characteristics
2.3.1 Overview
2.3.2 Storage Temperature
2.3.3 Storage Time
2.3.4 Storage Humidity
2.4 Cycle Life
2.4.1 Overview
2.4.2 Ambient Temperature
2.4.3 Overcharge
2.4.4 Deep Discharge
2.5 Safety
2.6 Characteristics of Various Series
2.6.1 Standard Series
2.6.2 High Drain Series
2.6.3 High Temperature Series
3 Charging Method
3.1 Overview
3.2 Charging Method
3.2.1 Constant Current Charging
3.2.2 Fast Charging
1
3
3
3
3
3
3
3
4
4
4
5
6
7
7
7
7
8
8
8
8
8
9
9
9
9
10
10
10
10
10
10
10
10
11
11
11
12
12
12
12
12
3.2.3 Charge Control
3.2.4 Standard Charge
3.2.5 Trickle Charging
3.2.6 Charging Temperature
4 Battery Assembly
4.1 Connection Between Cells
4.2 Thermal Protection for Battery Packs
12
13
13
13
14
14
14
5 Configurations
15
6 Proper Use and Handling
16
6.1 Restriction On Usage
6.1.1 Charging / Discharging Current
6.1.2 Reverse Charging
6.1.3 Parallel Charging
6.1.4 Charging / Discharging Temperature
6.1.5 Over-discharging / Overcharging
6.2 Precautions for Designing Application Devices
6.2.1 Battery Compartment
6.2.2 Charging / Discharging / Operating Temperature
6.3 Methods of Use
6.3.1 Operation
6.3.2 Connection Between Battery and Application Devices
6.4 Precautions in Battery Handling
6.5 Battery Maintenance
6.5.1 Regular Inspection
6.5.2 Storage
6.5.3 Battery Disposal
6.5.4 Transportation
16
16
16
16
16
17
17
17
17
17
17
17
18
18
18
18
18
18
7 Customer Application Questionnaire
19
8 Glossary
21
NOTICE TO READERS
The information in this technical handbook is generally descriptive only, and is not intended to make or imply any guarantee
or warranty with respect to any cells and batteries. Cell and battery designs are subject to modification without prior notice.
Performance of a battery should be based on its corresponding data sheet and product specification.
2
1 Introduction
1.1 Overview
1.1.1 Chemistry - the early days
Nickel metal-hydride (NiMH) technology has been
used commercially since the early 1990's, mainly
with consumer applications. At the time, nickel
cadmium (NiCd) was the mainstream technology
to which NiMHs was often compared. Even in the
early days, it was recognised that NiMH batteries
not only able to achieve higher energy density than
NiCds, also more environmentally friendly.
Since both systems employed 1.2V in nominal
vo l t a g e a n d a l s o s h a r e m a ny p e r fo r m a n c e
characteristics, it was relatively easy to adapt NiCd
applications for use with NiMH.
Subtle differences between the two chemical
systems made direct substitution of NiCd by NiMH
a difficult process. Differences in the charging curve
profiles meant that modification was required for
fast charging of NiMH batteries. The early NiMH
batteries were generally considered weaker in
charge retention perfor mance, and were not
deemed suitable for high-drain applications.
1.1.2 Well established product series
Over the years, there have been significant
improvements in NiMH technology, with most of
the ear ly weaknesses now eliminated. NiMH
batteries of today outperform NiCds in many areas,
including continued advances in energy density.
There are now NiMH batteries that have twice the
energy density of similar-sized NiCds, and many
new applications are designed specifically for NiMH
battery use, including: cellular phones, camcorders,
audio-visual equipment, toys, laptop computer and
personal care products.
GP NiMH rechargeable batteries had long been
established as a well-known choice that offers
perfor mance, reliability and value. We have
expanded our NiMH product range into various
ser ies to custom fit var ious application
requirements.
-- the ever popular standard series is designed
for a wide variety of general applications, including
toys, personal audio equipment, cameras and
cordless phones.
3
-- for capacity demanding applications, our high
capacity series is available. This has been
a c h i eve d t h r o u g h r evo l u t i o n a r y d e s i g n s i n
m e c h a n i c a l c o n s t r u c t i o n a n d n ew c h e m i c a l
formulation.
-- the high-temperature series is designed for
applications whereby the battery may encounter
elevated temperature during operation. Special
designs ensure that the battery performance is
stable and reliable under adverse environmental
conditions. Emergency lighting is one of such
applications best served by the high-temperature
series.
-- the high-drain series is expertly customized
for powerful delivery of electrical energy on demand.
Power tools and electric bicycles are among some
of the applications that excel with our high-drain
series as power sources.
1.2 NiMH Chemistry
1.2.1 Principle
As with any other rechargeable battery system,
NiMH batter ies operate on the pr inciple that
electrochemical reactions at each of the electrodes
are reversible; this enables energy to be stored
during charging and released during discharging.
1.2.2 Positive electrode chemistry
The reaction that occurs at the positive electrode
of a NiMH battery is the same as that for its NiCd
counterpart:
Ni(OH)2 + OH
NiOOH + H2O + e (during charging)
NiOOH + H2O + e
Ni(OH)2 + OH (during discharging)
Ni(OH) 2 and NiOOH are viewed as a reversible
couple, able to transform from one to the other,
depending on whether charging or discharging is
in effect.
During the charging operation, electrical energy
provided from an external power source is stored
as chemical energy in the cell, when the lower
energy Ni(OH) 2 is converted to the higher energy
NiOOH. During a discharge reaction, the NiOOH
is converted back to Ni(OH) 2, releasing the stored
chemical energy as electrical energy.
1.2.3 Negative electrode chemistry
The active material in the negative electrode is an
alloy, which can reversibly absorb and release
hydrogen atoms. There is no free hydrogen gas
involved in the charging and discharging of the
electrode.
There are two basic types of hydrogen-storage
alloys available for NiMH batteries. One type
consists of transition metals, such as titanium and
zirconium, often referred to as the AB 2 alloys. The
second type is made up of the rare-earth elements
such as lanthanum, known as the AB 5 alloys.
The following reactions occur during the charge
and discharge operations:
M + H2O + e
MH + OH
-
MH + OH (during charging)
M + H2O + e (during discharging)
In the equations above, M represents the hydrogenstorage alloy. MH is formed when hydrogen atoms,
from the electrolysis of water, are absorbed by the
alloy M. Upon discharge, the hydrogen atom is
released and converted back to water.
1.2.4 Overall reaction
Combining the equations in 1.2.2 and 1.2.3 reveals
the overall cell equation.
charging
Ni(OH) 2 + M
NiOOH + MH
discharging
The overall reaction schematically depicts a simple
transfer of H atom between Ni(OH) 2 and M,
depending on whether the cell is being charged or
discharged.
1.2.5 C e l l p r e s s u r e m a n ag e m e n t - ch a rg e
reserve
Up till now, only those reactions involving the main
charging and discharging process have been
shown. However, when a NiMH cell is close to
being fully charged, gas-generating side reactions
start to develop. For hermetically sealed batteries,
if the side reactions are not prevented, the internal
pressure may become excessively high.
ensure that the capacity of the negative electrode
exceeds that of the positive electrode. The excess
capacity in the negative electrode is referred to as
the charge-reser ve of the cell. With the proper
designs, the positive electrode is always the
capacity-limiting electrode. As the cell approaches
full charge, oxygen gas will star t to evolve from
the positive electrode in the process of electrolysis.
4OH
-
O2(g) + 2H2O + 4e
-
However, due to the excess capacity (chargereser ve) in the negative electrode, the
corresponding electrolysis product of hydrogen will
be prevented from forming. Instead, the oxygen
gas from the positive electrode diffuses to the
negative electrode and is consumed in the oxygen
recombination reaction.
The oxygen recombination at the negative electrode
o c c u r s s i m u l t a n e o u s l y, v i a t w o r e a c t i o n
mechanisms:
4MH + O 2
4M + 2H 2O
O 2 + 2H 2O + 4e
4OH
The first equation represents a direct combination
of the O2 gas with MH, which is present in significant
amounts at the negative electrode of a fully charged
battery. The second equation is a reverse of the
electrolysis reaction that originally generated the
O 2 at the positive electrode. The end result of these
two equations is that gaseous O 2 is reabsorbed by
t h e n e g a t i ve e l e c t r o d e, t h e r e by p r eve n t i n g
unacceptably high internal pressure during the
charging reactions.
In addition, most hermetically sealed rechargeable
batteries are equipped with resealable or nonresealable (one time) venting systems, which safely
release any internal pressure that might have built
up when the batter ies were exposed to
unexpectedly severe conditions of operations.
In sealed NiMH as well as NiCd batteries, the
internal pressure is designed to remain at safe
levels during operation. The main principle is to
4
1.3 Cell Construction
1.2.6 M i n i m i s i n g d a m a g e d u r i n g d e e p
discharge - discharge reserve
In the event of deep discharge, depreciation of
battery performance may occur. To minimise the
possibility of damage, the excess capacity in the
negative electrode also acts as discharge-reserve,
preventing the negative electrode from being
oxidised in the event that the battery is deeply
discharged.
Cylindrical
Cell cap (+)
Gasket
Safety-vent
system
Top insulator
Current
collector
Separator
Positive nickel
electrode (+)
Cell can (–)
The relationship between the useful capacity,
charge reserve and discharge reserve is shown in
the following schematic representation.
Bottom
insulator
Negative
hydride
electrode (–)
Positive Electrode
Ni(OH)2 / NiOOH
9V
Useful Capacity
M/MH
Discharge
Reserve
Negative Electrode
Positive pole
Plastic plate
Charge
Reserve
Metal jacket
Insulation paper
Metallic label
Positive weld
tag
Plastic plate
Prismatic
Negative pole
Top cup
In cell spacer
Negative contact
plate
Middle cup
Positive contact
plate
O-ring
Negative
electrode plate
Separator
Positive
electrode
plate
Electrode
sandwich
(1 Unit)
Positive terminal & safety vent
Lid
Gasket
Spacer
Positive electrode
Connector
Separator
Negative
electrode
Case ( negative
terminal)
5
6
Charge Voltage & Temperature of NiMH
When almost fully charged, peak voltage is attained.
However, if the battery is overcharged, a slight
decrease in voltage occurs; this arises from a
temperature increase due to the exothermic oxygen
recombination reaction. As a result, inter nal
pressure builds up and heat is generated during
overcharging. At a low charge rate (such as 0.1C
or below), equilibrium pressure can be attained
through a balanced electrode design. In addition,
heat generated during overcharging is dissipated
into the environment. The battery temperature is
a l s o a f fe c t e d by t h e c u r r e n t a n d a m b i e n t
temperature.
50
1.4
44
1.3
38
1C
1.2
7
0.5C
Cell temperature
0.1C
32
1.1
26
1.0
Input % of Nominal Capacity
Charging Characteristics at
Different Temperature
1C charging
1.7
80
0˚C Room temperature˚C 40˚C
70
1.6
Voltage
1.5
60
50
1.4
1.3
40
Temperature
30
1.2
20
1.1
10
1.0
Capacity Discharged at 20°C (%)
2.2.1 Overview
The nominal discharge voltage of a NiMH battery
is 1.2V at 0.2C discharge, which is almost identical
to that of a NiCd battery. The discharge time of a
NiMH cell is almost 1.5 times that of the NiCd cell
of same size, due to the high energy density of
NiMH batteries.
2.2.4 Polarity reversal during over-discharge
Most real-life applications employ multi-cell, series
- connected batteries. When discharging, the lowest
capacity cell will be the first to experience a voltage
drop. If the battery discharge continues, this unit
cell will be driven into an over-discharged condition.
When the cell voltage drops below 0V, its polarity
is effectively reversed. The cell reaction, at different
stages, is illustrated below:
20
0 10 20 30 40 50 60 70 80 90 100 110 120
0
0
2.1.2 Charging efficiency
In general, it is more efficient to charge the battery
at or below room temperature, since the chemicals
of both positive and negative electrodes are more
stable at lower temperatures - resulting in higher
discharge capacity. The charging efficiency of
standard ser ies NiMH batter ies drops rapidly
when the ambient temperature exceeds 40°C.
Furthermore, the decrease is more pronounced at
low charging rates, since the return of electrode
chemicals to their lower charge state is more
evident. The high temperature series, on the other
hand, allow applications of tr ickle charge at
temperatures as high as 70°C. The technology is
a result of dedicated research by GP to enhance
the stability of battery materials at high
temperatures.
Cell voltage
1.5
Temperature (˚C)
Temperature: 25˚C
2.2 Discharge Characteristics
56
20
40
60
80
100
Input % of Nominal Capacity
120
Charge-Temperature Characteristics
of Standard Series
105
100
95
90
85
80
75
70
65
60
0
Charge: 0.5C x 120%
Discharge: 1.5C to 1.0V
Temperature: 20°C
10
20
30
Charging Temperature (°C)
40
Temperature(˚C)
2.1.1 Overview
The charging process aims to restore the battery
for use by charging the batter y externally. The
charge voltage is affected by current, ambient
temperature and time. At the same ambient
temperature, the basic principle is: the higher the
current, the higher the charge voltage as a result
of increased over-potential at both electrodes.
Voltage (V)
2.1 Charging Characteristics
Charging Voltage (V)
1.6
2.2.2 Discharge voltage
The discharge voltage is affected by current and
ambient temperature. Like NiCd batteries, the
discharge voltage of NiMH batteries is depressed
at lower temperatures. This is because both NiCd
and NiMH batteries employ an aqueous electrolyte
system, resulting in decreased ionic mobility at
l owe r t e m p e ra t u r e s. A t h i g h e r c u r r e n t s, t h e
discharge voltage of NiMH batteries is depressed,
since the metal-hydride electrode is more polarised.
P r ev i o u s l y, m o s t N i M H c e l l m a n u fa c t u r e r s
recommended 3C as the maximum discharge
current; otherwise the discharge voltage would
have simply been too low for many applications.
As a result of advancements in NiMH batter y
technology, the discharge current achieved by some
of the latest NiMH batteries can now achieve as
high as 10C.
2.2.3 Discharge capacity
The discharge capacity is defined as “the product
of discharge current and discharge time when the
battery reaches the end discharge voltage.” The
nominal discharge capacity is rated at 0.2C to an
end voltage of 1V after charging at 0.1C for 14 16 hours.
The discharge capacity is also affected by discharge
c u r r e n t a n d a m b i e n t t e m p e ra t u r e. C a p a c i t y
decreases with decreased temperature due to lower
reactivity of the active materials and higher internal
impedance. At a higher discharge current, the
usable capacity is reduced due to larger IR drop,
and also because the battery voltage drops off
more rapidly to end voltage.
Stage 1: Initially, both positive and negative
electrodes, as well as the discharge voltage are
normal.
Stage 2: The active mater ial on the positive
electrode has been completely discharged and
evolution of hydrogen occurs. Cell pressure builds
up, although part of the gas can be absorbed by
the negative metal alloy electrode. Since the battery
i s d e s i g n e d w i t h ex c e s s n e g a t i ve c a p a c i t y
(discharge reser ve), the discharge continues;
discharge voltage is around -0.2V to -0.4V.
Stage 3: The active material on both electrodes
has been depleted and oxygen generation starts
at the negative electrode. Formation of gases at
both electrodes leads to high internal cell pressure
and opening of the safety vent, resulting in
deterioration of the cell performance if this scenario
occurs repeatedly.
Discharge Curves at Various
Temperature at 1.0C Rate
Charging: 0.1C x 120% at room temperature
1.5
Voltage (V)
2 Performance
Characteristics
1.4
1.3
1.2
1.1
10˚C 50˚C
25˚C
-10˚C 0˚C
1.0
0.9
0.8
0
20
40
60
80
Capacity Discharged (%)
100
120
8
Charge: 0.1C x 140%
Discharge: 0.2C, 1.0C, 2.0C, 3.0C
Temperature: 25˚C
1.4
Voltage (V)
1.3
0.2C
1C
1.2
1.1
2C
1.0
3C
0.9
0
20
40
60
80
Capacity Discharged (%)
100
120
Polarity Reversal
Battery Voltage (V)
1
Positive electrode
2
3
Negative electrode
1.0
0
Electrode Voltage (V)
-1.0
1.0
Positive electrode
0
-1.0
Negative electrode
Polarity reversal
of positive
electrode
Polarity reversal
of both
electrode
a. Decomposition of nickel hydroxide in the
positive electrode:
The nickel hydroxide is relatively unstable in a
charged state and tends to return to a discharge
state with the slow released of oxygen. The released
oxygen then reacts with the hydrogen in the
negative electrode, thus establishing an internal
discharge path. The reaction rate increases with
higher temperatures.
b . Release of hydrog en from the negative
electrode:
There is a very low hydrogen equilibrium pressure
for the metal-hydride electrode; such hydrogen
reacts with the positive electrode. After consumption
of the hydrogen, it is replenished from the metalhydride electrode and the reaction continues at a
steady rate. The reaction rate depends on the
hydrogen equilibrium pressure, which is higher at
increased temperatures.
c. Side reactions through impurities:
Some of the impurities can be oxidised in the
positive electrode when it migrates to the negative
electrode, where it reverts to its original form. The
shuttle reaction of the impurities dissipates the
battery's power during storage. The reaction rate
is also temperature-dependent.
Discharge Time
To avoid deep discharging, the capacity variation
of the battery pack's unit cells should be kept to
a minimum. It is also recommended that the
discharge end voltage should be maintained at
1.0V times the number of unit cells connected in
the battery pack. For battery packs connected with
more than 8 cells in series, the recommended
discharge end voltage is 1.2V times the number
of cells, less by one.
2.3 Storage Characteristics
2.3.1 Overview
The battery loses its energy during storage, even
without loading. The energy is lost through small,
9
2.3.2 Storage temperature
As already mentioned, the self-discharge reaction
rate increases with higher temperatures. Prolonged
storage of the battery at elevated temperatures will
result in the battery material deteriorating faster;
leakage performance will also deteriorate, resulting
in a reduced battery lifetime. It is recommended
that, for long storage, batteries should be kept at
room temperature or below.
2.3.3 Storage time
As the battery loses energy during storage, the
voltage also drops. In general, the battery capacity
loss due to self-discharge during storage can be
recovered by recharging. If the battery is stored
for over six months it is advisable to cycle the
battery several times to resume the battery capacity.
Storage Characteristics
100
0°C
80
25°C
60
40
20
Discharge: 1.0C (E.V. 1.0V) at 25°C
0
0
50
100
Storage Time (days)
45°C
150
200
2.4.3 Overcharge
The cycle life of the batter y is sensitive to the
amount of overcharge at high charge rate. The
amount of overcharge affects cell temperature and
oxygen pressure inside the battery. Both factors
deteriorate the metal-hydride electrode through
oxidation and thus the cycle life shortens. For that
reason the cycle life is affected by various charge
cut-off methods.
2.4.4 Deep discharge
The cycle life is also affected by the depth of
discharge. The number of charge/discharge cycles
will decrease if the battery is repeatedly subjected
to deep discharging below 1V, or to a status of
polarity reversal. Considerably more cycle numbers
can be obtained if the batter y is cycled under
shallower cycling conditions.
Cycle life of NiMH
2.4 Cycle Life
2.4.1 Overview
Cycle life is the number of charges and discharges
a battery can achieve before the discharge capacity
(0.2C) drops to 60% of the nominal capacity per
IEC 61951-2 or other guaranteed value per GP
specifications. Cycle life is affected by ambient
temperature, as well as depth of charge and
discharge. A common phenomenon to the NiMH
batter y is that the impedance increases upon
cycling due to electrolyte dry-out, especially at the
end of the cycle life. During overcharging, gases
form and pressure builds up inside the battery;
trace amounts of gas escape through the seal or
vent hole, leading to moisture loss and separator
dry-out. Actually, NiMH battery can attain 500-1000
cycles with cycling conditions of 0.1C charge/0.2C
discharge.
2.4.2 Ambient temperature
It is recommended to cycle the battery at room
temperature. At higher temperatures, the electrodes
as well as the separator material deteriorate much
faster, thus shor tening the cycle life. At lower
temperatures, the rate of oxygen recombination
during overcharge is slow, and may risk opening
the vent leading to pre-mature electrolyte dry-out.
110
% of Nominal Capacity
1.5
2.3.4 Storage humidity
Leakage and rusting of metal parts are accelerated
in high humidity environments, especially those
with correspondingly high temperatures. The
recommended humidity level for battery storage is
a maximum of 60% RH.
Retained Capacity (%)
self-discharge currents inside the batter y, as
explained below:
Discharge Characteristics
100
-dV=2mV/cell
90
-dV=30mV/cell
80
Time=120%
70
60
0
100
200
300 400 500
Number of Cycles
600
700
800
2.5 Safety
If pressure inside the battery rises as a result of
improper use, such as overcharge, shor t circuit,
or reverse charging, a resealable safety vent will
function to release the pressure, thus protecting
the battery from bursting.
2.6 Characteristics of Various
Series
GP NiMH rechargeable batteries had long been
established as a well-known choice that offers
performance, reliability and value. In order to widen
10
2.6.1 Standard Series
Our standard series is designed for a wide variety
o f g e n e r a l a p p l i c a t i o n s , w h i c h fe a t u r e s a
combination of superior positive and negative
electrode, allowing us to provide the highest levels
of capacity and quality for each size. These NiMH
b a t t e r i e s a l s o fe a t u r e ex c e l l e n t d i s c h a r g e
performance, low internal resistance and reliable
characteristics across a wide range of
temperatures, and they have been carefully
designed for safety and reliability. Ranging from
compact sizes to large sizes, the standard series
is available in a wide selection of discharge
capacities based on the standard sizes specified
in IEC61951-2.
2.6.2 High Drain Series
Our high drain series is exper tly customized for
powerful delivery of electrical energy on demand.
It was developed through an integration of our
c o m p r e h e n s i v e N i M H b a t t e r y t e c h n o l o g y.
Improvements in the positive and negative electrode
technology, and in the current collecting system
have further lowered the internal resistance and
greatly enhance the 10C discharge characteristics
of the high drain series batteries.
- Reliable, long cycle life
In addition to excellent high rate discharge
perfor mance, high drain series batteries also
provide hundreds of charge/discharge cycles,
showing reliable cycle life characteristics.
2.6.3 High Temperature Series
With standard series NiMH batteries, the smaller
the charging current and the higher the charging
temperature, the more difficult for it to charge the
battery. However, for applications in which the
batteries are charged continuously by a small
current under relatively high temperature conditions
such as emergency lights, there is a need for
super ior high temperature tr ickle charge
performance. By combining GP's technology in
electrodes and electrolyte, high temperature series
NiMH batteries are far superior to the standard
series NiMH batteries for use in high temperature
trickle charge applications. Furthermore, the use
of a special separator provides stable trickle charge
life characteristics.
Charge / Discharge Characteristics
of High Temperature Series
120
Available Capacity (%)
i t s f i e l d o f a p p l i c a t i o n s a n d ex t e n d i t s f u l l
advantages, we have expanded our NiMH product
range into various series to custom fit various
application requirements.
3C
10
20
30
40
50
60
Charge and Discharge Temperature (˚C)
70
Life Expectancy
8
40
60
80
Efficiency (%)
100
120
- Excellent high current discharge characteristics
It is designed to meet the need for high current
discharge, such as for power tools, and can deliver
a high current exceeding 10C.
11
Charge : 0.05C x 48 hours at stated temperature
Discharge : 0.2C to 1.0V cut off
20
Permanent Charge at 0.05C
10C
20
40
Charge: 1C x 120%
Temperature: 25˚C
5C
0
60
0
Years before end of life
Voltage (V)
1C
80
0
Discharge Curves of High Drain Series
at Various Rates
1.4
1.35
1.3
1.25
1.2
1.15
1.1
1.05
1.0
100
7
6
5
4
3
2
3 Charging
Method
3.1 Overview
One crucial difference between the primary and
secondary battery is the ability to restore energy
after discharging. This restoration of energy is
therefore a very important area to be considered
in secondary battery applications. Since different
battery systems have their own characteristics and
applications have their own integrated electrical
input/output requirements, it is vital to select a
charging method that suits both the battery system
and the application. Improper charging will lead to
p o o r b a t t e r y p e r fo r m a n c e o r fa i l u r e o f t h e
application.
3.2 Charging Method
Like NiCd, the main concern in charging a NiMH
battery is the build-up of temperature and internal
p r e s s u r e d u e t o h i g h ove r c h a r g e ra t e s. A s
previously mentioned, the cell design applies the
concept of oxygen recombination in lowering the
batter y's internal oxygen level during standard
charging. However, if the cell is subjected to severe
charging conditions (such as overcharging at a
current rate over 1C), the rate of oxygen evolution
from the positive electrode increases rapidly,
exceeding the recombination reaction rate. As the
oxygen recombination reaction is exothermic, this
results in excessive oxygen pressure and increased
temperature. The excessive pressure will then be
r e l e a s e d t h r o u g h t h e s a fe t y ve n t c a u s i n g a
reduction in the cell electrolyte; the excessive heat
will eventually degrade the cell's internal contents.
These two factors are considered to be the major
limitations to the battery's service life. For this
reason, charge control is very important in battery
charging. GP NiMH cylindrical cells are designed
to be able to charge up to 1C rate. For applications
that require higher charging rates, please contact
GP.
1
0
20
30
40
Cell Temperature (°C)
50
60
In secondar y batter y charging the two most
commonly used methods are constant voltage
charging and constant current charging. As with
the NiCd system, constant voltage charging is not
recommended for NiMH, due to thermal runaway
under overcharging conditions. As mentioned
earlier, the heat generated by the overcharge
current can cause a significant rise in batter y
temperature, which will cause a drop in the battery
charging voltage. In constant voltage charging, the
overcharge current is determined by the potential
difference between the power source and the
battery charging voltage. The increased difference
between the power source and the battery charging
voltage, due to the temperature rise, will also
augment the overcharge current. This increase in
the overcharge current will lead to a further increase
in cell temperature. This positive feedback cycle
of cell temperature and overcharge current will not
run down until the battery fails or until the current
limit of the charger is reached. For this reason,
constant voltage charging should not be used in
charging NiMH batteries, and charge control should
be employed if this method cannot be avoided.
3.2.1 Constant current charging
The advantages of the constant current charging
method include high charging efficiency, flexibility,
and position control of input capacity.
3.2.2 Fast charging
GP NiMH batteries use constant current charging
as the basis of the charging method. Depending
on different operational requirements, constant
current charging can be further classified according
to the charging rate. Charging at a current rate of
0.5C to 1C, or higher (up to 3C), is considered fast
charging. As explained earlier, if the charging
current is too high (1C or above), the cell internal
pressure and temperature will rise at the end,
r e s u l t i n g i n d e gra d e d c e l l p e r fo r m a n c e a n d
electrolyte leakage.
3.2.3 Charge control
Various methods are recommended to help control
charging, so as to prevent gas pressure and
temperature build-up due to overcharging. Proper
charge control will provide a longer battery service
life.
End life - 75% of the nominal capacity
12
a) dT/dt control
The detection of the rate of temperature rise when
the battery approaches a state of full charge (dT/dt
control) is considered to be the best form of charge
control. When charging at a current rate of 0.5C
to 0.9C, a temperature rate change of 0.8°C/min.
is recommended for charge termination; for 1C to
3C a higher rate of 0.8-1°C/min. should be chosen.
b ) -dV control
Detecting the value of the voltage drop after
reaching peak voltage is the most commonly used
charge control method in fast charging GP NiMH
batteries. A -dV value of 0-5mV/cell is recommended
when fast charging GP NiMH batteries, while a
-dV value of 2mV/cell is found to provide the best
balance between charge termination and service
life performance.
c) Charging time control (back up only)
An easier way to control fast charging of GP NiMH
batteries is to control the elapsed time following
commencement of charging. However, it is not
recommended as the only cut-off method due to
overcharging. A charging time equal to 105% of
the cell nominal capacity is recommended.
3.2.5 Trickle charging
In most applications - where cells and batteries
need to be in a fully charged condition - maintaining
a trickle charge current to compensate for the loss
of capacity (due to self-discharge) is recommended.
The suggested trickle charge current to be used
is 0.05C to 0.1C.
3.2.6 Charging temperature
As ambient temperature affects charging efficiency
and cell reliability, it is important to select a suitable
temperature for optimising charging performances.
Generally speaking, a temperature within 10°C to
45°C will yield the highest efficiency, which begins
to drop at or above 45°C. Conversely, repeated
charging at less than 0°C may cause cell internal
pressure build-up, resulting in electrolyte leakage
as in high temperature conditions. For these
reasons, GP NiMH batteries can be charged at
temperatures of 0°C to 45°C under standard
charging conditions, but preferably at 10°C to 45°C
under fast charging conditions
4 Battery
Assembly
4.2 Thermal Protection for
Battery Packs
4.1 Connections Between
Cells
The resistance spot-welding method is to be used
when NiMH cells are connected in a series, to
avoid an excessive increase in cell temperature,
which would occur if soldered on directly. Leads
used for cell connections should be nickel-plated
or pure nickel measuring 0.1mm to 0.4mm in
thickness and 3mm to 6mm in width.
The temperature of NiMH cells rises when the
charge gets close to completion. Temperature
increase is greater for a battery pack than for a
single cell, due to the fact that the pack does not
really allow for the dissipation of heat. The problem
is further exacerbated when the pack is enclosed
in a plastic case. Air ventilation should be provided
in the plastic case of batteries – to allow for egress
of any gases that may result from activation of the
safety vent of cells after abuse.
d ) Battery temperature control
As increased ambient and cell temperatures result
i n h i g h c e l l i n t e r n a l p r e s s u r e, i t i s h i g h l y
recommended to have temperature control backup
for safety and cell performance. When fast charging
GP NiMH batteries, the cut-off temperature is
recommended to be controlled at 45-50°C.
3.2.4 Standard charge
Apart from fast charging, GP NiMH batteries can
also be charged at a lower current rate of 0.1C. As
this charging method is less severe, charge
ter mination at 160% nominal capacity input is
recommended (to help avoid extended overcharging
of the battery). Also, in some applications where
overcharging is necessary, GP NiMH batteries can
endure 0.1C continuous charging for about one
year.
(+)
Polyswitch
Thermal protector
Thermistor
)–(
Single cell
Terminal plate
(Nickel)
Polyswitch
Thermistor
13
Battery packs intended for fast charging methods
s h o u l d h ave a t h e r m a l p r o t e c t i o n d ev i c e. A
thermistor sensing the temperature inside the pack
should be employed. It is also desirable to have a
thermostat/polyswitch and a thermal fuse installed
in the battery pack to protect it from abnormal rises
in temperature and exter nal shor t-circuiting.
Locations for safety devices in batter y pack
assembly are shown in the following diagrams.
Tape or
heat-shrinkable
tube
14
5 Configurations
Designation System for Battery Packs
An example:
Number of cells
Tag type code
in a pack
GP130AAM4BIP
Model number
Configuration Tag direction
code
code
For battery packs with connectors, the last two characters will be used to
specify connector type eg. GP130AAM4BMU.
Standard Configurations for Battery Packs
CODE : A
CODE : B
CODE : G
CODE : S
CODE : T
CODE : W
CODE : Y
Cells stacked in a
vertical column
Cells arranged
in a row
Cells stacked in 2
vertical columns
of unequal number
of cells
Cells stacked
in multiple
columns and
layers
Cells arranged in a
horizontal triangle
Cells arranged in
horizontal zig-zag rows
(in one or more layers)
Cells arranged in a
horizontal rectangle
Tag Direction Codes
Tag Type Specifications
CODE : 1
CODE : 2
CODE : 3
CODE : 4
CODE : 5
CODE : 6
CODE : P
CODE : H
Strip solder tag
PCB solder tag
Double PCB pin
at positive terminal
and single PCB pin
at negative terminal
Solder wire tag
Short strip tag
Lead wire
Pointing at 180˚
Pointing at the
same direction
Connector Type Specifications
GP Universal Plug - exclusively from GP, offers distinctive features unparalleled in the market.
- U.S. patent no. 5,161,990.
Major Benefits
• Compatible with most cordless phone models
(interchangeable with Mitsumi, JST, Molex plugs etc.)
• Minimise inventory items
• User friendly
MU
Universal Plug
15
MJ
JST EHR-2
ML
Molex 5264-02
Use and
6 Proper
Handling
6.1 Restriction on Usage
Knowledge of battery maintenance is crucial to a
working battery, helping to provide a longer period
of operation. On the other hand, improper battery
handling or maintenance may lead to unnecessary
battery defects or problems, such as electrolyte
leakage or cell bulging. In order to get the most
out of using GP NiMH rechargeable cells, special
care in the following areas should be considered:
6.1.1 Charging / discharging current
For fast charging GP NiMH batteries, the current
rate should be 0.5C to 1C. Trickle charging, which
is common in various applications (such as memory
backup), requires a current charging range of 0.05C
to 0.1C to maintain the long-term standby power
of the battery. In addition, GP NiMH batteries can
be trickle-charged at 0.1C continuously for one
year without leakage or explosions. Charging
current rates higher than 1C are generally not
recommended. However charging with pulses higher
than 1C is not uncommon in some applications.
Please contact authorised GP personnel to
determine the applicability of special charging
schemes not mentioned in GP product
specifications.
These charging cut-off mechanisms can be
incorporated into the application – either together
or individually, with the choice of method depending
largely on the charging profile of the application.
To avoid unnecessar y batter y problems, which
might look like quality issues, please contact
authorized GP personnel for implementing the
appropriate charging cut-off method.
A wide range of required discharge current rates
will be encountered in different applications, and
GP has a variety of battery types for specialised
use. Apar t from the standard series for general
applications, high temperature and high drain series
are specially designed for applications in high
ambient temperatures and discharge current rates
respectively. The maximum discharge current
recommended for batteries of standard series is
generally 3C. However, there are situations where
higher currents of shorter duration are permissible.
6.1.2 Reverse charging
Reverse charging is one of the battery misuses
that can appear to be a battery defect. If the positive
and negative polarities are reversed when charging,
the battery might bulge due to internal gassing.
Electrolyte leakage consequently results due to
venting at the safety valve, which leads to a
decrease in capacity. Caution has to be exercised
to avoid such misuse.
Special attention should be paid to the charge
termination method, which is a critical element in
providing an optimised cycle life, yet one which is
e a s i l y ove r l o o ke d . S eve ra l c h a r g i n g c u t - o f f
mechanisms with related parameters can be
considered:
6.1.3 Parallel charging
Parallel charging is generally not recommended,
please consult authorized GP personnel for possible
exceptions to connecting the batteries in parallel
charging.
Negative delta voltage: 0-5mV
dT/dt:
0.8°C/minute (0.5C to 0.9C)
0.8-1°C/minute (1C)
Temperature control:
45-50°C
Timer control:
105%
6.1.4 Charging / discharging temperature
I t i s i m p o r t a n t t o u n d e r s t a n d h ow a m b i e n t
temperature affects the charging and discharging
of batteries, especially for obtaining maximum
e f f i c i e n c y i n c o n d i t i o n s t h a t ex c e e d r o o m
t e m p e ra t u r e. G P r e c o m m e n d s t h e fo l l ow i n g
temperature range.
MS
Mitsumi M63M83-02
16
Standard, high drain and high capacity series cylindrical / prismatic / 9V
Standard charge:
Fast charge:
Discharge:
Storage:
0°C to 45°C
10°C to 45°C
-20°C to 50°C
-20°C to 35°C
High temperature series - cylindrical
Standard charge:
Discharge:
Storage:
0°C to 70°C
-20°C to 70°C
-20°C to 35°C
Using or stor ing the batter y beyond the
recommended temperature range leads to
deterioration in performance. For example: leakage,
shortening of battery life, and lowering of charging
efficiency may occur at higher temperatures.
At sub-zero temperatures, discharge capacity will
decrease due to lower mobility of the ions inside
the battery.
6.1.5 Over-discharging / overcharging
Other than discharging C-rate and temperature,
another factor affecting battery life and performance
is the discharge cut-off voltage. An appropriate
choice of end voltage not only determines the
battery performance, it also provides the bottom
line to avoid over-discharging the batter y. GP
recommends 1V/cell as the end voltage in most
situations. However, there are occasions when
slightly higher than 1V/cell is necessary (to avoid
scenarios such as over-discharge, when the number
of batteries in the series is large). In addition,
discharge cut-off lower than 1V/cell should be
considered especially when the discharge rate is
very high.
Overcharging also adversely affect battery life, the
major cause of which is the extra heat generated
by overcharging. When overcharging repeats from
cycle to cycle, the accumulated heat will eventually
degrade the battery life. Therefore, incorporating
a proper charging cut-off mechanism is a critical
element in ensuring a long battery life.
17
6.2 Precautions for Designing
Application Devices
6.4 Precautions in Battery
Handling
6.2.1 Battery compartment
Bear in mind that there is always a chance of
battery abuse, where internal gassing is highly
probable; and as a result, the gas will be released
through cell venting. However, generation of
hydrogen gases from overcharging is particularly
dangerous when mixed with oxygen. Caution should
b e fo c u s e d o n t h e v e n t i l a t i o n o f b a t t e r y
compartments. Airtight battery compartments are
strongly discouraged. Ventilation should be provided
in the plastic case of batteries, otherwise oxygen
and hydrogen gas generated inside can cause
explosion when exposed to fire sources such as
motors or switches.
•
•
•
6.2.2 Charging / discharging / operating temperature
To optimise battery performance and service life,
cer tain aspects related to charging, discharging
and the operating temperature should be taken
into careful consideration. A customer application
q u e s t i o n n a i r e i s p r ov i d e d i n t h i s t e c h n i c a l
handbook. Please provide as much information as
possible. Alter natively, contact authorized GP
personnel for advice and help with your application.
6.3 Methods of Use
6.3.1 Operation
Avoid combining used and fresh batteries, or
batteries at different state-of-charge, which may
lead to electrolyte leakage. Always cycle the battery
several times to restore its capacity if the battery
has been stored for an extended period of time.
6.3.2 Connection between battery and application
devices
Be sure to connect the positive and negative battery
terminals to the corresponding terminals of the
application device, in order to prevent reverse
charging.
•
•
•
•
•
•
•
•
•
•
•
•
Never incinerate the battery.
Never solder a battery directly.
Avoid subjecting a battery to strong vibrations,
pressure or impact.
Never connect the battery terminals to the device
without verifying the polarities.
Never carr y a batter y with other metallic
belongings to avoid short-circuiting.
Never disassemble a battery.
Never mix GP batteries with other battery brands
or batteries of a different type.
Never short together the positive and negative
terminals of a battery with any metal.
Never obstruct the safety vent, which is located
near the positive terminal of the cylindrical/
prismatic cell, and on the positive side of the
button cell -indicated by a vent mark.
N eve r a l t e r t h e fa c t o r y - c o n f i g u r a t i o n o r
remove/modify a component of a battery.
N eve r c h a r g e / d i s c h a r g e a b a t t e r y u n d e r
conditions which are not within GP
specifications, or without consulting authorized
GP personnel on special applications.
Never use other charger than specified to avoid
possible heating, burning or rupture.
Never leave a battery connected to a device for
long per iods without charging the batter y,
especially for devices that constantly drain
standby current.
If any abnormality or problem is found while using
the battery, stop its use, and bring it to your local
dealer.
Never use cells or batteries for any other applications
than specified, that may result in damage to the
batteries and the appliances.
6.5.2 Storage
Bear in mind that self-discharge has to be taken
into consideration when storing a charged battery.
The remaining battery capacity should be at least
50% after a month of storage at room temperature
fo r a f u l l y c h a r g e d b a t t e r y. H i g h s t o r a g e
temperatures will accelerate the self-discharge,
and reduce the remaining capacity.
In order to maintain batter y performance when
being stored for an extended period of time, cycling
(charging and discharging) of the battery within a
6 to 9 month period is recommended. This
procedure is recommended to maximize
performance of the battery and prevent low OCV
in long-term storage conditions. Failure to do so
may result in a shorter battery life.
6.5.3 Battery disposal
Under normal conditions, when the battery has
reached its end of life, it is advisable to properly
insulate the positive and negative terminals of the
batter y prior to disposal. Please note that it is
dangerous to dispose of the battery in fire, as it
will lead to electrolyte spill-out and bursting of the
battery.
Recycling of the battery is an impor tant
environmental issue nowadays. We recommend
you contact your local government concerning the
location of recycling sites, or enquire about local
regulations on methods of disposal for NiMH
batteries in your region.
6.5.4 Transportation
GP NiMH batteries should not be thought of as wet
batteries (like traditional, non valve-regulated
batteries). As a result, GP batteries can be shipped
or transported in normal packaging without special
hand.
6.5 Battery Maintenance
6.5.1 Regular inspection
Pe r i o d i c v i s u a l i n s p e c t i o n o f t h e b a t t e r y i s
recommended. It is also advisable to store the
battery at room temperature, with low humidity,
when the battery is not expected to be used for a
long period of time; the aim of which is to prevent
cell leakage and rust.
18
7 Customer Application Questionnaire
Cap#
Customer:
Address:
Customer:
Salesperson:
Sales Order#
Contact person:
Electrical:
Mechanical:
Commercial:
Customer:
Salesperson:
Sales Order#
Title:
Title:
Title:
Charge Mode
Charge
Constant
current (mA)
Tel:
Tel:
Email:
Tel:
Max. volts
(V)
-Delta V
(mV/cell)
DV/dt
(mV/min)
N/A
N/A
N/A
N/A
Ultra Fast (>2C)
Fast (>0.5C)
Standard (0.1C)
Trickle (<0.1C)
Date:
Email:
Email:
Termination
Cell qty:
Pack qty:
D. Type of designs:
Preliminary
E. Ship to:
Salesperson
Others
Name:
Address:
City:
F. Specifications: (from customer)
Customer drawing:
Parts & asssembly drawing:
Written specification:
Others: (please specify)
Current to voltage limit (mA)
mAh Voltage:
Tentative production date:
V
N/A
Voltage limit (V)
(<4.2V/cell)
Time
(hr)
4.2
2.5
Standard (0.8C) to 4.2V
Charge control
chip
Final
Over charge
limit (V)
Over discharge
limit (V)
Over discharge
current limit (A)
Over discharge current
delay time (mins)
TCO
(°C)
Timer
(hr)
* The
method of charging and discharging Li-ion battery is very important to the safety and performance of the battery. Please consult engineer
for optimal safety and performance.
State:
Zip:
For Smart Battery
Fuel Gauge Parameter Table (provided by customer)
IC Type (provided by customer)
Yes:
(please attached)
Remarks:
(pcs).
Bill of material:
Date:
Customer sample(s):
Circuit diagram:
Title:
Details:
1. S h ow a l l c r i t i c a l d i m e n s i o n w i t h
tolerance or max.
2. Show connector polarity.
3. Show label orientation.
4. Show and list any special features or
materials.
Sketch
I. Discharge method
Discharge mode: Constant current
Average current
Power
Resistance
Discharge termination method: Cut off voltage
J. Operation temperature
mA
mA
W
Ohm
No:
Battery low alarm voltage
Discharging cut-off voltage
Stand-by current after cut-off
mV
mV
mA
(V)
Max.
Min.
In charge
In discharge
In storage
Rating
Manufacturer
Model no.
°C
Ohms
°C/Amps
A
* All Packs should be protected against short circuit and over charging.
* Li-ion packs must have safety circuit to protect over charging.
* Air ventilation should be provided in the plastic case of batteries, otherwise it may have a risk generating gases inside them (oxygen and hydrogen
gas) resulting explosion triggered by fire sources (motors or switches). Caution should be focused on the ventilation of battery compartments.
Airtight battery compartments are strongly discouraged.
19
N/A
N/A
Vmax
(V)
Safety Protection
Company:
G. Protection / Safety:
Customer will protect battery externally.
Built-in protection requirements
Component
Short circuit
Overcharge
Polyswitch:
Thermostat:
Thermistor:
Thermal fuse:
Current fuse:
Others:
Timer
(hr)
Customer proposed
Requested delivery date:
Electrical only
DT/dt
(°C/min)
Charge
II. Product Description
Capacity:
Qty/year:
Quote:
Testing:
Mechanical only
TCO
(°C)
For Li-ion
Charge Mode
A. Model No.:
B. Application:
C. Sample request:
Date:
For NiCd & NiMH
I. Customer Information
City:
State:
Zip:
Fax:
Cap#
H. Charging parameter
*Fill out as much of the following table as possible.
K. Specific testing requirement:
Please describe
III. Remarks
IV. Approvals
Sales:
(GP internal use only)
Engineering:
20
8 Glossary
Active Material
Chemicals that give rise to electro-chemical
reactions, and which generate electrical energy in
the battery.
Charge Retention
The percentage of capacity remaining after a
charged cell/battery has been stored for a period
of time.
Negative Electrode
The electrode with negative potential. Current flows
through the external circuit to this electrode during
discharge.
Alkaline Electrolyte
An aqueous alkaline solution (such as potassium
hydroxide) which provides a medium for the ionic
conduction between the positive and negative
electrodes of a cell.
Closed-circuit Voltage
The voltage of the cell/battery with loading.
Nominal Voltage
A general value to indicate the voltage of a battery
in application.
Ampere-hour
Unit of capacity of a cell/battery. Capacity is defined
as the product of the discharge rate and the
discharge time.
C-Rate
Relative rate used in cell/battery, defined as the
quotient of current (mA)/nominal capacity (mAh).
Constant Current Charging
Charging with a fixed current value.
Battery
Consists of one or more connected cells.
Cut-off Voltage
A set voltage that determines when the discharging
of a cell/battery should end.
Capacity
The amount of electrical energy that can be
supplied by a cell/battery - expressed in mAh, and
in specified discharge conditions.
Cycle Life
The number of cycles a cell/battery can run under
specific conditions, while still delivering specified
minimum capacity.
Cell
An electrochemical unit constituting positive and
negative electrodes, separator, and electrolyte to
provide electrical energy.
Depth of Discharge
The percentage of the available capacity from a
cell/battery during discharge.
Cell Reversal
In reversal, the normal terminal polarities of a cell
in a multiple cell battery are switched. Cell reversal
normally occurs only if three of more unit cells are
connected, and the battery is deeply discharged.
Cell reversal is detrimental to performance, and
should be avoided by proper selection of cut-off
voltages during discharge.
Discharge
The operation which removes stored electrical
energy from a cell/battery.
Discharge Rate
The rate of current drained from a cell/battery.
Electrode
A conducting plate containing active materials.
Charge
The operation which inputs electrical energy to a
cell/battery.
Exothermic Reaction
A chemical reaction which results in the release
of heat energy as it proceeds.
Charge Efficiency
A measurement of accumulated efficiency during
the charging operation.
Memory Effect
The phenomenon whereby the capacity of a cell
may be temporarily decreased when it is repeatedly
used in a shallow discharge pattern. Memory effects
are erased when the cell is discharged to the
nor mal cut-off voltage (e.g. 1.0V at the 0.2C
discharge rate).
Charge Rate
The rate of current supplied to a cell/battery.
21
Open-circuit Voltage
The voltage of the cell/battery without loading.
Overcharge
The continued charging of a cell/battery after it is
fully charged.
Positive Electrode
The electrode with positive potential from which
current flows through the external circuit to the
negative electrode during discharge.
Standard Charge
The normal charge rate used to charge a cell/battery
in 16 hours. Normally 0.1C.
Thermal Fuse
A component assembled into batteries, which
breaks the current when the temperature reaches
a predetermined value.
Thermistor
A component with a negative temperature coefficient built into batteries and/or used to detect the ambient
and battery temperature.
Trickle Charge
A continuous and very low rate charging to keep
a cell/battery on full capacity.
Overcharge Current
The charge current supplied during overcharge.
Cells/batteries can accept continuous overcharging
at recommended rates and temperatures specified
by the manufacturer.
Rated Capacity
A nominal capacity available from a cell at specific
discharge conditions.
Safety Vent
This is a device to release the gas when the internal
pressure of the battery exceeds the pre-set value.
Self-discharge
The loss of capacity by a cell/battery during storage
or in an unused condition. The rate of self-discharge
is affected by ambient temperature.
Separator
The thin and porous membrane between the
positive and negative electrodes to prevent shortcircuit and hold the electrolyte.
Short Circuit
The direct connection of the positive electrode/
terminal to the negative electrode/terminal of the
battery.
22
8/F., Gold Peak Building, 30 Kwai Wing Road, Kwai Chung, N.T., Hong Kong
Tel : (852) 2484 3333 Fax : (852) 2480 5912
E-mail address : [email protected] Website : www.gpbatteries.com.hk
SALES AND MARKETING BRANCH OFFICES
ASEAN
GP BATTERY MARKETING (SINGAPORE) PTE. LIMITED
97 Pioneer Road, Singapore 639579
Tel: (65) 6863 1534 Fax: (65) 6863 8669
MALAYSIA
GP BATTERY MARKETING (MALAYSIA) SDN. BHD.
Lot 26, Jalan Pengapit 15/19, Shah Alam Industrial Estate,
40000 Shah Alam, Selangor Darul Ehsan, Malaysia
Tel: (60) 3 5512 5675 Fax: (60) 3 5510 4543
THAILAND
GP BATTERY MARKETING (THAILAND) CO., LIMITED
3/F., VH Commercial Building, 23/1 Soi 9, Ngamwongwan Road,
Nonthaburi 11000, Bangkok, Thailand.
Tel: (66) 2 952 5323/5324 Fax: (66) 2 952 5322
TAIWAN
GP BATTERY MARKETING (TAIWAN) LIMITED
Room 1200, International Trade Building, No.205 Sec.1,
Tun Hua South Road,Taipei 10647, Taiwan R.O.C.
Tel: (886) 2 2741 4919 Fax: (886) 2 2731 4868
CHINA
HUIZHOU CHAO BA BATTERY TECHNOLOGY CO., LTD.
2/F., South of Hongye Industrial Building,
Tianluo Mountain, 14th Industrial District, Huizhou City,
Guangdong, China (Postal Code: 516003)
Tel: (86) 752 282 8428 Fax: (86) 752 280 2872
HONG KONG
GP BATTERY MARKETING (H.K.) LIMITED
8/F., Gold Peak Building, 30 Kwai Wing Road,
Kwai Chung, N.T., Hong Kong
Tel : (852) 2420 0281 Fax: (852) 2494 9349
KOREA
GP BATTERY MARKETING (KOREA) LIMITED
4/F., Kunsul Hoekwan Building, 71-2 Non Hyun-Dong,
Kang Nam-Gu, Seoul, South Korea
Tel: (82) 2 549 7188/9 Fax: (82) 2 514 0623
U.S.A.
GOLD PEAK INDUSTRIES (NORTH AMERICA) INC.
11235 West Bernardo Court, San Diego,
CA 92127-1638, U.S.A.
Tel: (1) 858 674 6099 Fax: (1) 858 674 6496
CANADA
GP BATTERY MARKETING INC.
Unit 7, 7780 Woodbine Avenue, Markham,
Ontario, Canada L3R 2N7
Tel: (1) 905 474 9507 Fax: (1) 905 474 9452
LATIN AMERICA
GP BATTERY MARKETING (LATIN AMERICA) INC.
8370 NW, 66TH Street, Miami, Florida 33166, U.S.A.
Tel: (1) 305 471 7717 Fax: (1) 305 471 7718
EUROPE
GP BATTERY MARKETING (EUROPE) S.A.
75 Zae Du Trou Grillon,
91280 St Pierre Du Perray, Paris, France
Tel: (33) 1 6989 6200 Fax: (33) 1 6989 6221
GERMANY
GP BATTERY MARKETING (GERMANY) GMBH
Niederlörricker Str. 62, D-40667 Meerbusch, Germany
Tel: (49) 2132 971504/5/6 Fax: (49) 2132 80145
POLAND
GP BATTERY (POLAND) SPÓLKA Z O.O.
uL. Sl owicza 19, 02-170 Warszawa, Poland
Tel: (48) 22 846 7525 Fax: (48) 22 846 7535
U.K.
GP BATTERIES (U.K.) LIMITED
Summerfield Avenue, Chelston Business Park,
Wellington, Somerset, TA21 9JF, U.K.
Tel: (44) 1 823 660 044 Fax: (44) 1 823 665 595
ITALY
GP BATTERY MARKETING ITALY S.R.L.
Via Enrico Fermi 8, 20090 Assago, Milano, Italy
Tel: (39) 02 488 2512 Fax: (39) 02 488 0275/2865
SCANDINAVIA
CEBON AB
Grimboåsen 5, 417 49 Gothenburg, Sweden
Tel: (46) 31 558 600 Fax: (46) 31 556 813
GPPA1THH-A 06/02
WORLDWIDE HEADQUARTERS
Hong Kong
GPI International Limited
All rights reserved. No parts of this catalogue written or pictorial may be reproduced without the permission of GPI International Ltd.
Nickel Metal Hydride
Technical
Hand Book
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