Lithium-ion battery pack capacity testing methods:
The first step is to fully charge the lithium-ion battery. A single lithium-ion battery has a voltage of 4.2V after being fully charged.
The second step is to use a multimeter to discharge the battery at a constant current (0.5C, relative to the battery capacity), setting the termination voltage to 3V;
The third step is to multiply the constant current discharge time by the discharge current to get the capacity of the lithium-ion battery pack;
To begin testing, first fully charge the battery with the charger; the full charge voltage is 4.2V. Then, use a multimeter as a constant current load to discharge it at 0.2C (i.e., 1000 × 0.2 = 200mA). Set the multimeter's discharge voltage to 3V. If the discharge time reaches 5 hours, the battery is considered合格 (qualified). Modern lithium-ion batteries can generally discharge down to 2.75V, while the depth of discharge is the same as before (3V as the cutoff voltage, 80%), yet it can be discharged for 8 hours, indicating an improvement in the power of lithium-ion battery packs.
0.2C is the international standard test method, but in practice, 0.5C is usually used. In this case, the multimeter is set to a constant current load of 500mA, and it must be able to reach 3V for more than two hours to be considered qualified.
