Battery in the fridge !!!

[overlander]

This was touched on in another thread but i think it warrants its own thread. If the figures are to be believed storing your battery in a fridge can significantly increase its lifespan with regards to natural deterioration due to time. For example 20% lose per year at room temp to 6% stored in a fridge.

So before i put my £450 battery in the freezer what are your views on this.

 

[flecc]

I have spelled this out many times, this is only for long term storage, never for a battery in use, and it really applies at a consistent almost zero degrees C. Most household fridges sit at 5 to 10 degrees varying. Actual freezing should never be done, it destroys the battery.

Therefore it will rarely apply to most e-bike owners. If a bike is to be laid up for the winter, yes, but if used fairly regularly, no.

To get the full advantage of the low temperature the battery should be down to about 40% charge, and the stresses of discharging, reducing temperature, then allowing temperature to get back to normal before use and recharging all have their own losses. Doing that regularly would drastically shorten the life.

I use my laptop on battery only about once a year, so it's lithium battery is clingfilm wrapped and in the base of the fridge at the back at around 3 degrees fairly constant. It's now in its sixth year and fine. If I'd put it in and out of cold storage frequently I'm sure it would have been wrecked within a year.
.

 

[overlander]

Thank you flecc that is clear as day, just have to accept that 2-3 years will be the usable life of the battery. Not too bad really considering the use it gets, to be honest with my use i.e charging 2 time a day from flat 2 years i would be happy.

 

[BLACKPANTHER]

So, am I better off keeping the battery in the house? At the moment I put the bike in the (tin) garage, and the battery gets charged in the house and kept under the stairs after each use. This means it is kept at a constant temp of 18-22 degrees, rather than below freezing in Winter and probably 30+degrees in Summer in the garage. I thought the battery performance went down when it was really cold?

 

[rustic]

So, am I better off keeping the battery in the house? At the moment I put the bike in the (tin) garage, and the battery gets charged in the house and kept under the stairs after each use. This means it is kept at a constant temp of 18-22 degrees, rather than below freezing in Winter and probably 30+degrees in Summer in the garage. I thought the battery performance went down when it was really cold?

30+ degrees in Doncaster!!

 

[overlander]

I also take the battery into the house at night, got that bit right

 

[BLACKPANTHER]

30+ degrees in Doncaster!!

In Summer in the tin shed it's like an oven! Surely that wouldn't do the battery any good?

 

[flecc]

So, am I better off keeping the battery in the house? At the moment I put the bike in the (tin) garage, and the battery gets charged in the house and kept under the stairs after each use. This means it is kept at a constant temp of 18-22 degrees, rather than below freezing in Winter and probably 30+degrees in Summer in the garage. I thought the battery performance went down when it was really cold?

Performance does indeed reduce in the cold, particularly below about 7 degrees C, so the battery will perform better if kept in the house. Therefore best to carry on as at present which won't reduce the life.
.

 

[overlander]

Performance does indeed reduce in the cold, particularly below about 7 degrees C, so the battery will perform better if kept in the house. Therefore best to carry on as at present which won't reduce the life.
.

From my own experience of using the bike a few times at -15 degrees there was no real noticeable decrease in performance. I reckon as you say there was a decrease but the battery meter resolution never picked up on this as i still arrived empty . Then again i had more things to worry about than measuring the battery thought my ears and nose were going to fall off.

 

[HarryB]

I normally have 2 or 3 lights at the end of my journey when I get to work or home. I could just about do the return journey of 20 miles but not a chance during the -4C weather (I know because I got caught out with a forgotten charge) and usually one flashing light at the end of my journey at this temp. So range when new - 26 miles, now over 20 miles or just over 10 when below freezing. I always bring my battery indoors but pop it in the fridge when I go on holiday in the summer.