C-rate refers to the charge/discharge current value ratio to the battery’s rated capacity.

The C-rate of the lithium-ion battery decides how fast the battery can be fully charged or how fast it can be fully discharged. By knowing the C-rate, people can tell the battery charge or discharge speed is fast or slow.

Take a 2000mAh lithium-ion battery as an example. Its rated capacity is 2000mAh.

If the discharge current is 2000mA, it will require 1 hour to be fully discharged, then the C-rate is 1C.

If the discharge current is 4000mA, then it will require 0.5 hours to be fully discharged, and the C-rate is 2C (4000mA/2000mA=2C)

If the discharge current is 400mA, then it will require 5 hours to be fully discharged, and the C-rate is 0.2C (400mA/2000mA=0.2C)

Herewith is the formula to make it more clear:

D-rate (C) = Charge/discharge current(A K))÷ Rated capacity(Ah)

When discharging with N times the current of the 1C capacity of the lithium battery, and its discharge capacity is more than 85% of the 1C capacity of the battery, we consider the discharge rate of the battery to be N times.

The C-rate of a battery is an important consideration when designing a charge or discharge system because it affects the battery’s performance and lifetime.

Zum Beispill, charging or discharging a battery at a high C rate will cause the battery to heat up and degrade faster, while charging or discharging at a low C rate can extend the life of the battery, but will take more time.

At present, the charging rate supported by lithium batteries is only 1.3C. Am Géigesaz, graphene fast charging batteries have 6C fast charging capabilities and can be charged to 85% in 8 minutes, which is equivalent to the time it takes to fill up a tank of fuel for a fuel vehicle.

Allgemeng, we call a lithium battery discharged at 1C a standard battery, a lithium battery discharged at 2C-10C a low-rate battery, and a lithium battery discharged over 10C a high-rate battery.

Lithium batteries are used in different products depending on the rate.

The high rate of the lithium battery is relative to the ordinary rate, representing the charge and discharge capacity of the lithium-ion polymer battery.

If an ordinary battery is charged quickly, it is easy to cause lithium precipitation at the negative electrode, resulting in accelerated performance degradation of the lithium battery. In severe cases, it may cause a short circuit inside the battery, causing a fire and explosion.

The charge and discharge rate performance of lithium batteries is directly related to the migration ability of lithium ions at the positive and negative electrodes, electrolyte, and the interface between them. All factors that affect the migration speed of lithium ions (these influencing factors can also be equivalent to the battery’s Internal resistance), will affect the charge and discharge rate performance of lithium-ion batteries.