In the context of lead-acid batteries, “0.5C” refers to a discharge or charge rate that is half of the battery’s capacity per hour. The term “C-rate” is used to describe the rate at which a battery is charged or discharged relative to its nominal capacity.
To understand 0.5C more clearly, let’s break it down with an example:
- Battery Capacity: Suppose you have a lead-acid battery with a nominal capacity of 100 ampere-hours (Ah).
- 0.5C Discharge Rate:
- A 0.5C discharge rate means the battery is discharged at a rate equal to half its capacity per hour.
- For a 100Ah battery, this would be 0.5 * 100Ah = 50A.
- Therefore, discharging the battery at 0.5C would mean drawing 50 amperes from the battery.
- Discharge Time:
- At a 0.5C discharge rate, the battery would theoretically take 2 hours to be fully discharged.
- This is because 100Ah / 50A = 2 hours.
- 0.5C Charge Rate:
- Similarly, a 0.5C charge rate means charging the battery at a rate of 50A.
- If you charge a 100Ah battery at 50A, it would theoretically take 2 hours to fully charge the battery, assuming 100% charging efficiency and no losses.
In summary, “0.5C” in lead-acid battery parameters indicates that the battery is being charged or discharged at a rate that would fully charge or discharge the battery in 2 hours if the process were perfectly efficient. This C-rate is crucial for understanding the performance, efficiency, and safe operating limits of the battery.
