2010 Prius, 59,500 miles. In service since October, 2009. Keeping an eye on the 12v battery, since I've heard many need replacement at around 5 years. Dealer checked battery at oil change with following results: Rated CCA 272 Measured CCA 565 Measured Volts 12.59 Degrees F 75 Delaer says "good", and I don't disagree. Is it surprising to find the battery this healthy under the circumstances? Was accidentally discharged, once, about 2 years ago.
The voltage looks good. The other numbers I know nothing about, lol. In your shoes, having had one accidental discharge, I'd replace it next fall. Just for peace of mind.
Cold cranking amperes (CCA) is the amount of current a battery can provide at 0 °F (−18 °C). The rating is defined as the current a lead-acid battery at that temperature can deliver for 30 seconds and maintain at least 1.2 volts per cell (7.2 volts for a 12-volt battery). It is a more demanding test than those at higher temperatures. This is the most widely used cranking measurement for comparison purposes. How can you measure this on a Prius that doesn't use the 12 volt battery to "crank" the engine? Probably some software derived junk number.
It is a way of expressing the LOAD TEST results in terms that most people are familiar with. Makes no difference if there really IS a starter present or not.
The voltage is fine, and the measured CCA's are fine as well.... just the rated CCA's are strangely low. The OEM battery should have been set to 325 CCA's afaik. If they set up the tester with a rated CCA of only 272, then the results are off using an induction type of load tester, they may have also messed up the battery construction type as well if they missed the correct CCA rating to test at. Roland
