Panasonic HHR200A - Manual (Page 3)

NICKEL METAL HYDRIDE HANDBOOK, PAGE 9 AUGUST 2005
Features
•••••
Similarity with Ni-Cd batteries
These batteries have similar discharge characteris-
tics to those of Ni-Cd batteries.
•••••
Double the energy density of conventional
batteries
Nickel-metal hydride batteries have approximately
double the capacity compared with Panasonic’s
standard Ni-Cd batteries.
•••••
Cycle life equivalent to 500 charge and
discharge cycles
Like Ni-Cd batteries, nickel-metal hydride batteries
can be repeatedly charged and discharged for about
500 cycles. (example: IEC charge and discharge
conditions)
•••••
Rapid charge in approx. 1 hour
Nickel-metal hydride batteries can be rapidly
charged in about an hour using a specially designed
charger.
•••••
Excellent discharge characteristics
Since the internal resistance of nickel-metal hydride
batteries is low, continuous high-rate discharge up to
3CmA is possible, similar to Ni-Cd batteries.
NICKEL METAL HYDRIDE BATTERIES - CONTINUED
Five Main Characteristics
As with Ni-Cd batteries, nickel-metal hydride batteries
have five main characteristics: charge, discharge,
storage life, cycle life and safety.
1) Charge characteristics
Like Ni-Cd batteries, the charge characteristics of nickel-
metal hydride batteries are affected by current, time and
temperature. The battery voltage rises when the charge
current is increased or when the temperature is low.
The charge efficiency differs depending on the current,
time, temperature and other factors.
Nickel-metal hydride batteries should be charged at a
temperature ranging from 0
°
C to 40
°
C using a constant
current of 1It or less. The charge efficiency is particularly
good at a temperature of 10
°
C to 30
°
C. Repeated
charge at high or low temperatures causes the battery
performance to deteriorate. Furthermore, repeated
overcharge should be avoided since it will downgrade
the battery performance.
Refer to the section on recommended charge methods
for details on how to charge the batteries.
•
Charge characteristics
•
Charge temperature characteristics at 1It charge
P-120AS
Ni-Cd
Discharge Capacity (mAh)
V
oltage (V)
1.6
1.4
1.2
1.0
0.8
0 200 400 600 800 1000 1200 1400 1600 1800 2000
1.8
HHR200A
Ni-MH
Size: KR17/43
Charge: 1CmA x 1.2h
Discharge: 0.2CmA
Temperature: 20˚C
HHR200A
Ni-MH
P-120AS
Ni-Cd
Discharge Current (A)
Capacity (mAh)
0 1 2 3 4 5
2200
2000
1800
1600
1400
1200
1000
800
600
400
Size: HR17/43
Charge: 1CmA x 1.2h
Temp.: 20˚C
Charge Capacity (%) (Nominal Capacity Ratio)
V
oltage (V)
0 20 40 60 80 100 120 140 160
Charge : 120%
Temperature: 20˚C
Model
: HHR200A
1It
0.33It
0.1It
2.0
1.8
1.6
1.4
1.2
1.0
0.8
0.6
Charge Capacity (%) (Nominal Capacity Ratio)
V
oltage (V)
1.6
1.4
1.2
1.0
0.8
0 20 40 60 80 100 120 140 160
Charge : 1CmA x 120%
Model : HHR200A
1.8
0.6
2.0
0˚C
20˚C
40˚C