New LiFePO4 32650 charged resting voltage


MASSIVE restock of EV Batteries at www.batteryhookup.com 5% coupon "POWERWALLS"

Delta-9

New member
Joined
Nov 26, 2020
Messages
14
I don't really have a purposefor this battery build, just experimenting with the chemistry and the cost factor (vs the other packs I've built from the 18650 Ring packs). I likely will just keep this thing around as a ~15-18Ah portable power bank.

I am waiting on an (aliexpress shipment) Daly BMS to connect to this pack. In the meantime, I spot-welded this thing up and used my bench DC power supply to bring each of these parallel groups up to 3.64V. The CC dropped to 0.0A on each of these before I disconnected them.I don't have any other charging option since these don't fit into the ZanFlare unit and the(TrustFire)charger I bought on Amazon was junk, so I sent it back.

Its been roughly 5-7 days since each of these parallelgroups have finished charging. Yesterday they all were sitting nicely in line around 3.5V and now today they are sitting at 3.48-3.49V.

Should I be worried about this slow creep? Is this normal for the LifePO4 chemistry ?


image_horget.jpg


New to this forum, figured I would say hello.
 

daromer

Moderator
Joined
Oct 8, 2016
Messages
5,662
Its normal. They can rest all between 3.4 to 3.45 in general. The lower the more used they tend to be but it doesnt have to be any big indication on more than some loss in capacity. They drop and act alot more like a lead acid in that sense except that 90% of the capacity curve is pretty darn flat :)

THere are some whitepapers about this somewhere.
 

Delta-9

New member
Joined
Nov 26, 2020
Messages
14
daromer said:
Its normal. They can rest all between 3.4 to 3.45 in general.

Awesome, thank you. Being that this is my first LiFePO4 pack build, they are behaving a little differently than the 18650 Li-ion do a few days after coming off the charger. Good to know its normal.
 

gpn

Member
Joined
Jan 21, 2018
Messages
251
I have a small 4s10p 26650 pack that i run from 3-3.45v per cell. They stay really well balanced in the range and i'm not really stressing it. My typical balance in that range is about .002v. When I push it higher or lower it starts to go out of whack. They were new cells and all from the same batch.


its fun to start building!
 
Top