Phylion battery, how often do you need to recharge when not in use?

[electron]

Hello,
I've not been using my bike for a couple of months and according to the battery (36v phylion) instructins I should recharge it for a few hours. The thing is, the battery power leds still indicate the battery is still highly charged (the three led are still lit). Do I still need to recharge (I read its not good to store the batteries at full charge, and a few hours should definitely be enough for a full recharge)? Is there a chance that the power indicator will show full but some of the batteries in the unit may be nearly drained?
thanks in advance!

 

[flecc]

They need to be recharged at least once every three months, preferably every two months for safety to avoid premature cell death. This is regardless of whether they appear full or not. Don't worry about full charge storage, there's no appreciable loss of life at normal temperatures, it's only at near to zero degrees storage that a 40% or similar storage level has much gain in life. You'll see from the Battery University site chart linked to below that at typical British average winter temperatures you'd only lose a few per cent of the capacity in a year storing fully charged. Only by refrigeration is any gain possible and then it's not enough to fret about:

Storage temperature chart
.

 

[Synthman]

My old Phylion battery has sat unused for 5 months. I fully charged it after I last used it, and all 10 battery cells are still over 4v. There has only been a 1.5v drop across the entire battery in that time.

 

[flecc]

That appears lucky Synthman, but no lithium battery maker would recommend taking that risk. The voltage on the cells can remain high but the battery fail as soon as a load is applied. I'd recommend you try it out on the road as soon as possible and afterwards recharge, rather than leave it any longer.

 

[Synthman]

That appears lucky Synthman, but no lithium battery maker would recommend taking that risk. The voltage on the cells can remain high but the battery fail as soon as a load is applied. I'd recommend you try it out on the road as soon as possible and afterwards recharge, rather than leave it any longer.

I can't be bothered as the battery was practically useless when I stopped using it, was cutting out under load very badly even at full charge. I want to see if its possible to remove the BMS and swap it with the one in my newer battery as it lacks the balancing feature.

 

[flecc]

As it was already dud the measured quiescent voltage had no meaning as I observed. It's very likely that one or more of the cells is dud anyway, so a BMS change won't necesarily help.

 

[Synthman]

No, I want the BMS from the old Phylion to put in my newer battery. The new battery's BMS lacks cell balancing.

 

[flecc]

Understood Synthman.

 

[Synthman]

I've managed to swap the BMS. They both have the same connectors, the BMS I salvaged from the Phylion is ever so slightly larger, but the main difference was the multi connector (the one with 10-12 coloured thin wires) emerges at a different angle. I managed to get it all assembled again and it works on the bike and I'm currently charging it and waiting to see what difference it makes.

What's the best way to dispose of the old battery?