I think Flecc keeps his laptop battery in the fridge and it's lasted years.
Yes, it's there now at about 5 degrees C and will be 6 years old next year.
Cold storage is only worth it for long terms though, I only travel with my laptop a couple of times a year for example. After each battery use I charge to about 20 to 40% and it goes back onto the floor of the fridge wrapped in clingfilm.
If using an e-bike at least once a month it's not worth it, the stress of contantly bringing the cells up to temperature and full charging will probably reduce the life as much as any saving made.
Most current e-bike lithium batteries are good for about two years life with usable range, a bit less sometimes if used daily for high mileages or a bit longer if intermittently used for lower mileages. They do chemically deteriorate with age though, so very light use doesn't mean very long life with full capacity.
It's not possible to define accurately how much capacity is lost per annum since the constant developments are improving this. It was originally about 35% of the year's starting capacity per annum lost, but that's probably down to under 20% with the best ones now.
All the above is for lithium batteries with manganese or compound cathodes. The not commonly used newest type with iron based cathodes (LiFePO
4, known as Lithium Iron Phosphate) can last around two or three times as long, depending on the application.
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