Discharge Rates using various C (capacity) ratings
|20 hour rate||126AH (6.3A)||100AH (5.0A)||72.0AH (3.6A)||46.0AH (2.3A)||27.2AH (1.4A)||17.0AH (0.8A)||18.0AH (0.9A)||13.9AH (0.7A)||14.8AH (0.74A)||8.0AH (0.4A)|
|10 hour rate||114AH (11.4A)||92AH (9.2A)||70.0AH (7.0A)||42.0AH (4.2A)||26.0AH (2.6A)||16.0AH (1.6A)||17.0AH (1.7A)||13.1AH (1.3A)||14.0AH (1.4A)||7.0AH (0.7A)|
|8 hour rate||110AH (13.7A)||90AH (11.2A)||67.2AH (8.4A)||40.8AH (5.1A)||25.6AH (3.2A)||15.7AH (2.0A)||16.7AH (2.1A)||12.9AH (1.6A)||13.6AH (1.7A)||7.6AH (9.5A)|
|5 hour rate||103AH (20.6A)||85AH (17.0A)||66.0AH (13.2A)||39.5AH (7.9A)||24.9AH (5.0A)||15.1AH (3.0A)||16.0AH (3.2A)||12.4AH (2.5A)||12.5AH (2.5A)||7.2AH (1.44A)|
|2 hour rate||90AH (45.0A)||80AH (40.0A)||60.0AH (30.2A)||37.8AH (12.6A)||24.1AH (8.0A)||14.4AH (4.8A)||15.3AH (5.1A)||11.8AH (3.9A)||11.8AH (5.9A)||6.5AH (3.25A)|
|1 hour rate||80AH (80.0A)||73AH (73.0A)||57.0AH (57.0A)||33.8AH (33.8A)||21.7AH (21.7A)||12.7AH (12.7A)||13.6AH (13.6A)||10.4AH (10.4A)||11.0AH (11.0A)||6.0AH (6.0A)|
|1/2 hour rate||69AH (138.0A)||60AH (120.0A)||51.5AH (103A)||30.4AH (60.8A)||19.5AH (39.0)||11.5AH (23.0A)||12.2AH (24.4A)||09.3AH (18.5A)||10.0AH (20.0A)||5.4AH (10.8A)|
Many different rates are quoted in marketing documentation to make you believe their batteries are better than other so use this chart to find the equal comparison.
Also worthy of mention is different rates are used in different industries and sometimes within different applications i.e. C20 is used for reserve batteries while the same battery is commonly quoted using the C10 rate for UPS discharge figures even though the batteries are commonly reviewed for their watts per 15 minutes rates.
Traction batteries (as they are referred to in the industry) are used in forklifts, electrically powered industrial applications are often referred to using the C5 rates as they will provide a higher amp rating figure for the duration of an eight hour shift (allowing for breaks and other delays in use during the work day).
Aviation batteries are commonly referred to in their Amp Hour rating but without noting the actual C rate. For the record in almost all cases the batteries discharge capabilities are calculated using the C1 rate (one-hour discharge rate) an example is PC680 being quoted by an auto electrician as an 18AH would technically be referred to as a 12.7AH battery by someone within the aviation industry to fairly compare against an alternative brand.