Battery voltage help - not charging

Planemo

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Jun 30, 2015
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Oops..embedded pic - I am not keen on links especially when I am asking for help.

 

Nealh

Esteemed Pedelecer
Aug 7, 2014
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I looked at the pic on PB, It appears you have 3 groups of cell packs for 10 cells which is strange for 10. I can only assume the black bit is a packing spacer on top of the final 2 cells by the looks of it.
 

Planemo

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Jun 30, 2015
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Hi Neal, you are correct there is a black packing foam spacer on top of 2 cells, the BMS is on top of another 2. So left to right there is 3 cells, 3 cells, 2 cells + 1 spacer on top then 2 cells + BMS on top. There are definatley 10 cells of (I guess) 1A each.

As an update, the 6th cell still hasn't reached 3.8v. It's currently hovering at 3.6v which concerns me as it has had around 1600mah pumped into it now. Its clearly dead. Not good, I was hoping it would take enough just so we can go on our family holiday with the bikes. Theres nothing to lose, I will top up the other cells as best they accept it, then charge the whole pack with the stock charger and see what I get. If we manage just a couple of rides it will be nice. I guess I will be on to someone who re-cells, I have seen a name on the forum but can't remember it now, will have a search. Gutted TBH, as is my wife of course :(

Thanks for everyones help.

Nathan
 

D8ve

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Jan 30, 2013
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Insat is the company's name. Don't top the other batteries up above no6's value. When you fit the main charger it will drive them all the same. It could cause a fire.
And all the batteries will be 10 000 mA so keep on charging no 6 you have a long way to go.
 

Planemo

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Jun 30, 2015
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Hi D8ve
Ah yes Insat I remember now.
No6 was left on overnight but still didnt hit more than 3.6v. Nuts. Looks like I will be contacting Insat very soon. Shame because I dont need much capacity from the wifes battery (she could probably get away with 7a) but it does obviously have to be working properly. Will see what they can offer, I certainly dont need all singing ultra capacity cells.
 
D

Deleted member 4366

Guest
Your battery is a normal lithium-ion pouch cell one, and is probably OK to give some amount of use in the future.

It takes almost no charge to raise any under-voltage cell to 3.0v, so they appear to go up quickly at first, but after that, at .2A it will take 50 hours to reach 4.2v or about 25 hours to reach 3.8v.

.2 amps is about right for under-voltage cells, but after they reach say 3.5v, you can increase the charge to 2 amps.
 

Planemo

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Jun 30, 2015
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Many thanks for all your help guys, I managed to get up to 3.6v on the bad cells, saw a total output of 37.2v and rebuilt the battery which is now charging on the stock charger. It is clear that the initial 31.8v was much too low to allow charging. All being well, what I am left with should be enough to get the Mrs moving so I am very happy, and should buy us enough time to worry about re-celling it later. It's been a bit of a pain getting this far, and is enough to make me treat batteries with a little more TLC in the future!
 

D8ve

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Jan 30, 2013
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Best balance the battery asap. You need to make sure you don't over charge the other cells.
 
D

Deleted member 4366

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It is clear that the initial 31.8v was much too low to allow charging.
No, it was the one cell at 1.7v that stopped the charging. Most BMSs won't allow charging if any cell goes below 2.5v.
 
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