53.3volts

[Low]

Hi, iv just completed build two.. So much better, really quite proud of it! Charging for the first time butchered an old 54.6er i got with my cyclitricity) i notice that it green lights at 53.3 volts, any ideas why im not getting to 54.6?

Ebay bms
48v 7p 13s battery with 25Rs
Charging via xt60s.

Was worried id made a bad spot weld or generally over looked somthing during the build, then did the maths and 53.3 \ 13 = 4.1

Seems quite the councidence that the voltage is so exact at 4.1, couod this just me the BMS set at 4.1? Or do i need to tear into the pack an re-check every thing

 

[LeighPing]

Great job.

 

[Low]

Thanks buddy, having the weight in the frame feels soo nice, got really lucky with the colour too... Who new specialized red was in fact hyundai sunbeam red!!

Going to gut the motor and battery from my cyclitricity steath next , but a nice high end ish 2nd hand 17inch mountain bike and build the missus one next... Should of done hers first really!

Anyone ever heard of s Bms calling it a day at 4.1?

 

[anotherkiwi]

It could do. You aren't losing much range between 4.2 and 4.1 it kind of drops down really quickly between those two values. These are your new cells? Ride some then charge again to see if you don't get 4.15 V would be my suggestion.

 

[Low]

Yes m8, they are all brand new cells, had a couple of very fast sparks during the build but nothing near any sort of runaway.

Interesting about discharge and charge.. Just went out for a short ride, 53.3.... Now charges to 53.5

Why is that?!?

 

[Deleted member 4366]

Your cells are a little out of balance - nothing to worry about. Balancing only happens at the top of the charge cycle. Each time you charge, they should get a bit better.

 

[Low]

Thanks D8v and thanks everyone, couldn't of done any of this without this site, brilliant teachings

Regards