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C Rating Calculator

What is C rating Calculated

C Rating is a fairly misunderstood concept in batteries. The C Rating is defined by the rate of time it takes to charge or discharge a battery. You can increase or decrease the rate which in turn will have an inverse effect on the time it takes to charge or discharge the battery. An example of this is if a battery amperage is 2000mAh or 2Ah and has a 1C rate, then it will take 60mins to charge or discharge the battery. 1C rating is the base time which is always equivalent to 1 hour or 60mins.

The C Rating's charge or discharge time changes proportionally to the rating. 1C is equal to 60mins, 2C is equivalent to 0.5h or 30mins and a 0.5C rating is equivalent to 2h or 120mins. The equation is simple. t = 1/Cr to view in hours or to view in minutes use time = 60mins / Cr (c rating)

Examples of Different C Rating Calculations

0.5C C Rating Example

2000mAh Battery
2000mAh / 1000 = 2A
0.5C x 2A = 1A available
60 / 0.5C = 120mins charge/discharge

2C C Rating Example

2000mAh Battery
2000mAh / 1000 = 2A
2C x 2A = 4A available
60 / 2C = 30mins charge/discharge

20C C Rating Example

2000mAh Battery
2000mAh / 1000 = 2A
20C x 2A = 40A available
60 / 20C = 3mins charge/discharge