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Charging
Charging circuits
Charging/discharging cycle Approx. 1,000 times at 10% discharge depth to nominal capacity Charging system* Constant-voltage charging.(Please strictly adhere to the specifi ed charge voltage)
Operating temperature -20 C ~ + 60 C* Consult with Panasonic concerning constant-current charging systems. The charging circuit is crucial in terms of ensuring that full justice will be done to the battery characteristics. Consider it carefully as the wrong charging circuit can cause trouble.
Precautions regarding the charge voltage setting
Under no circumstances should trickle charging, which is used for nickel-cadmium batteries, be used. Ignoring this precaution will cause the battery voltage to rise to about 5V, resulting in a deterioration of performance.
VL0V5V VL0V
3.4V3.6V Chapter 3 wrong right Charge voltage range
If a fi xed-charging method is applied, please adhere to the specifi ed charging voltage.
The guaranteed value over an operating temperature range from -20 to +60C is 3.4V 0.15V.(Actual value: 3.4V 0.20V)* If the charging voltage exceeds the specifi cations, the internal resistance of the battery will rise and may cause battery deterioration. Also,with a charge voltage around 4V, corrosion of the (+) terminal (case) may occur, causing leakage. ("Infl uence of the charge voltage on VL batteries" in Chapter 3-59.) * It is not possible for the battery capacity to recover completely when the charging voltage is below the specifi cation.
Vanadium Pentoxide Lithium Coin Type Batteries (VL series) Basic conditionsCharge voltage: 3.4V0.15VCharge current: For a battery voltage of 3V
VL621 Approx. 0.2 mA or below VL1216, VL1220 Approx. 0.5 mA or below
VL2020 Approx. 1.5 mA or below
VL2320, VL2330 Approx. 2.0 mA or belowVL3032 Approx. 4.0 mA or below
Recommended charging circuits
(It is permissible for the current to increase beyond the above level when the battery voltage drops below 3V.)
Mixed usage of batteries
Do not use these batteries and lithium primary batteries or other rechargeable batteries together, and do not use new batteries and old batteries together even if they are of the same type.
Chapter 3- 57