How much is an MHEV battery?

I'm thinking of buying a fairly new used car. Most of them seem to have mild hybrid engines, but I haven't found information on how long these batteries last and how much they cost to replace. As I understand it they are all 48 volt.
Do you have any information on this?

Asked on 12 February 2024 by V

Answered by David Ross
Mild hybrid technology is now commonplace on petrol and diesel engines, providing improved economy and performance. Mild hybrids have very small battery packs compared to full hybrids and EVs, and at no point is the car driven solely on electric power, so the performance of the car is affected very little by the condition of the battery. We would expect it to last for many years without replacement, so although a replacement would be more expensive than a conventional 12V battery, unless you plan to keep the car for 10 years or more we would not expect this to be an issue.
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