C-rate

C-rate tells you how fast a battery can be charged or discharged. A battery's nominal capacity always comes with the discharge time it was measured at. Stationary batteries are usually rated by their C10 capacity, which is the capacity over a 10-hour discharge. For example, a battery rated C10 = 200 Ah can be discharged for 10 hours at 0.1 × C10, which is a nominal current of 20 A. The capacity you get depends on the discharge time. SMA gives factors to estimate C10 from other ratings: C10 = C100 / 1.25, C10 = C5 / 0.88 and C10 = C1 / 0.61. Battery and inverter spec sheets list continuous power separately from surge (peak) power. Peak power covers short events such as starting large appliances. The Sunny Island 4548-US shows this split: it is rated 4,500 W continuous and 11,000 W for 3 seconds at 25°C. Its continuous charging current is 85 A, and its maximum charging current is 110 A.

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• sentence 5: support check: partial - Passages show continuous vs surge/peak power on spec sheets, but nothing about inverter spec sheets or peak covering short events like starting appliances beyond the washer/dryer image title. -->