Lithium Battery Charging Method

GB/T18287 2000 Lithium ion Battery regulation:

a. Lithium ion battery: rated voltage 3.7/3.6V, charge cut-off voltage 4.2/4.1V, according to design of different cell brands.

b. Battery charging method: first CC, constant charge current, and Battery Voltage rise step by step as charge process goes on; change to CV, when battery voltage up to 4.2/4.1V, constant voltage, and charge current will decline as process goes on. Charge cut-off when charge current drops to 0.01C.

c. 0.01C cut-off charge current is regulation of GB/T18287-2000, though YD/T998-1999 regulation is 20mA. No matter how large battery capacity is, charge cut-off current is 20mA. Now GB regulation 0.01C good for battery fully charged, also for manufacturer pass appraisal. Besides, GB regulation, charge time must less than 8 hours.

d. What is the proper charge current? In theory, the lower the current, the better for lithium-ion battery; GB standard for energy type battery is 0.2C, e.g. for 1000mAh battery, standard charge current is 200mA, fully charged time will be around 5 hours.

About there is a wrong opinion about Lithium Battery charge: that charge & discharge time is limitation, so recharge after mobile battery fully discharged.

In normal situation, you should not follow the principle that recharge battery after surplus electricity volume consume complete. Provided your battery would not hold for next whole day, you should start recharge in time; and you need recharge battery to deal with future busy communication, even battery with lots of surplus electricity volume, so recharge battery in advance, that you have not lost a charge cycle life exactly. The principle that recharge battery after surplus electricity volume consume complete, is not leading you to extreme .

Another saying, try to use mobile battery electricity volume complete, auto cut-off will be best. This practice is for nickel metal hydride battery; aim to avoid memory effect, unfortunately it also for lithium ion battery.

Someone avoids the alter that mobile battery electricity volume too low, keep using until auto cut-off, and then there is no responds boot after recharged. This is because battery over discharge so as to voltage too low, that without normal charge and boot condition.

Life experiment shows, scrap rate is 50% for lithium battery that deep discharge 100%.