Formula: Battery charge and discharge rate in amps = Battery capacity (Ah) × C-rate let's say you have a 100ah lead-acid battery. 100Ah lead-acid battery has a recommended charge and discharge rate of 5 amps let's say you have a 100ah lithium battery. 100Ah lithium-ion battery has a recommended charge and discharge rate of 50 amps
For example, if a battery has a capacity of 3 amp-hours and can be discharged in 1 hour, its discharge rate would be 3 amps. The battery discharge rate is the amount of current that a battery can provide in a given time. It is usually expressed in amperes (A) or milliamperes (mA).
The battery that we have has a minimum C rate of 0.2C. So, a battery with a lower C rate is needed in this application. You can easily calculate the maximum charge/discharge current of a battery from its C rating. Just multiply the battery capacity with the C-rating mentioned on the battery back.
If the above batteries are discharged at a 2C rate, they will discharge within 30 minutes. At 4C rate, they will take 15 minutes to discharge, and so on. It’s possible to discharge a battery at a C rate of less than 1. At C/2 rate, it will discharge in 2 hours. At C/4 rate, it will take 4 hours, and so on.
If a battery is being charged at 5 amps and has an energy rating of 20 Ah, the C rate is calculated as: \ [ C\ Rate = \frac {5} {20} = 0.25\ C \] This means the battery is being charged at a rate that is one-quarter of its total capacity per hour.
For example, let’s say you have a 100-watt-hour lead-acid Battery that provides 90 watt hours over 10 hours at room temperature (20°C). To calculate its efficiency, divide 90 by 100 and multiply by 100% – giving you an answer of 90%. What is the Typical Battery Discharge Rate? A battery’s discharge rate is the rate at which it loses charge.