battery charge

[robdon]

I have a new battery 36 volt 15ah which will only take 39.5 volts when fully charged, this is measured at the output pins of the battery, have tried to charge more but charger shows green, charger output 42 volts.
anyone know what is wrong, I read that it should charge to 42 volts.
ROB

 

[jackhandy]

just a stab in the dark...

Cold weather, maybe: Try charging somewhere q bit warmer.

 

[robdon]

it`s not been in the cold , kept indoors.
ROB

 

[patpatbut]

BMS in the battery shut off possibly. Try to charge it overnight to see if it helps. If not, you might need to open the battery case to check each cell.

How old is the battery btw?

Pat

 

[robdon]

new never been on a bike or any thing else.


ROB

 

[Deleted member 4366]

Could we have some details of what battery it is? A link would help.

 

[D C]

I would check your meter is accurate before going further, I've been led astray by faulty measuring equipment in the past.
Apologies if you've done this already.

 

[Oxygen Bicycles]

is the battery performing ok? Is it cutting off when running low?

 

[jackhandy]

new never been on a bike or any thing else.

More coffee

 

[robdon]

information on battery : 36 volt 15 ah external fuse on handle,
Diamond Power LI-ION BATTERY
International Development Ltd
dpowercar@gmail.com
batteries 5 in a row blue colour with barcode 7 cm long
ROB

 

[patpatbut]

Have you check the voltage out from your charger using voltmeter?

 

[robdon]

yes
voltage from output of charger 42 volts
ROB

 

[Deleted member 4366]

information on battery : 36 volt 15 ah external fuse on handle,
Diamond Power LI-ION BATTERY
International Development Ltd
dpowercar@gmail.com
batteries 5 in a row blue colour with barcode 7 cm long
ROB

if you want some help give us a 'kin link to the thing.

 

[robdon]

what`s a kin link
ROB

 

[robdon]

sorry
it is a lithium li-ion 36v 15 ah

 

[pdarnett]

I think Dave means where did you buy it from, paste the link in so we can do a little investigation. Some pictures of the pack might help as well.

 

[robdon]

bought on ebay for £210.00 had just come from China, person had just paid
£40+ for courier and taxes, everything in the box was spanking new

ROB

 

[Deleted member 4366]

I would start by measuring the voltage from the battery and the charger with the same voltmeter. Please report the two results here.

Without a picture of the battery, it's very difficult to give you exact help, but the next test would be to measure the battery voltage at the charge socket.

 

[robdon]

charger output 42.2 volts
battery output pins 39.1 volts
at battery charging socket 38.6 volts
ROB

 

[robdon]

it is nearly the same as this in looks

ROB