Battery temp & range - warm vs cold

[Mudgey]

Hello,

So two of us went out for the first time on very similar electric bikes, on one the battery was kept in the house and the other was kept at work. Probably 18c vs 5-8c. The cold battery seemed to be going down pretty quickly, other factors were at play such as tyre pressures, rider weight etc. However, would a temperature difference such as this have a noticeable effect on how quick the battery would deplete?
Both sets of batteries are now at the house, is it worth ensuring they are kept here and charged inside before a ride?

 

[Nickolp1974]

Wouldn't of thought it would make a bit of difference as they will both be at the same temp within minutes of being in the cold air/wind.

 

[Kingfisher]

It's complicated.

In summer, under heavy use, batteries suffer from overheating. The BMS (battery management system) is very sensitive to temperature.
But batteries hate cold. First, NEVER let your battery freeze, sure way to kill it. You can use it in frost, as the use will create heat. But don't store the bike outside overnight in winter.

So, with 5-8c: Battery life will be reduced, untill the battery starts heating up from use. Keeping the battery inside is better (as your empirical, though anecdotal, findings point out)

 

[Mikerb]

Definitely better to both store and charge lithium batteries at room temperature. For those riding in extreme cold temperatures a neoprene cover on the downtube may help initial battery warm up and heat conservation when taking a break.

 

[Mudgey]

Thanks for the replies. The batteries now live in doors. They are both quite a lump and the new one took quite a while to warm up!
I think a cover isn’t a bad idea to wrap round the battery, even if it’s just to keep it clean when out riding.

 

[grantini]

Who makes neoprene covers? Or if it’s self made some guidance?

 

[Mikerb]

Look up neoprene battery cover on google or Amazon...loads of options

 

[Peaky Rider]

Who makes neoprene covers? Or if it’s self made some guidance?

I wanted one to go around the battery and down-tube on my Canyon Spectral. My main concern was to keep muck and water out of the battery cradle as well as keeping the battery clean and dry. Any warming effects would be a bonus.

Couldn't find anything commercially available so made my own.

£10 worth of neoprene and £5 worth of Velcro off Ebay, two made and enough material left over for several more.

Really pleased with how efficiently it works and I don't think it looks too stupid.

 

[KennyB]

If it looks stupid and it works, it isn't stupid.

 

[Guyt]

I wanted one to go around the battery and down-tube on my Canyon Spectral. My main concern was to keep muck and water out of the battery cradle as well as keeping the battery clean and dry. Any warming effects would be a bonus.

Couldn't find anything commercially available so made my own.

£10 worth of neoprene and £5 worth of Velcro off Ebay, two made and enough material left over for several more.

Really pleased with how efficiently it works and I don't think it looks too stupid.
View attachment 23470

Good job, custom is the way to go if one wants a perfect fit. My wife is really good in that type of work, I'll ask her to make one for my fatbike I use in the winter in -20C to 0C temperature. But I never charge the battery if it's below 10C.