Looking at my battery build for a BBSHD. I am looking at a 52v battery 14s4p

 

Is or has anyone tried a 15s setup, I was thinking a 15s setup and charge the pack to 60v max which will mean each cell will charged to 4v.

 

I am lead to belive that the controller will take a max of 63v.

 

Are there any disadvantages to doing this, it will only mean four extra cells in the pack.

 

Any recommendations for a BMS for a BBSHD.

52v is 14S. Yes they can run with that.

Yes. but will the system be happy on 15s battery with out any ill effects .

As long as you don't exceed 62V it will run OK.

several ES members have done this.

I’m thinking of a 14 or 15 s system and using my normal 48V, (54.6V) charger 14s = 58.8V and 15s = 83V. The idea being to 80/90% charge up longer life.

Preparing the cells for assembly is a drawn out affair. Testing all the cells first . Internal resistance, capacity and voltage to be within 1/10th volt to avoid electron flow and potential heat . The Opus BT-C3100 I recommend but with four slots and 3.5 day testing times a hundred batteries will take for ever.

Would it be a good idea to utilise ( for instance) a 10s bms withe battery holders and discharge modules each , make a ten cell capacity and recharging unit.

Internal resistance is a quick in out test but capacity check is slow. Maybe place a thermistor on each cell too so nothing hot or cold. Store for a month and check for lost volts. Bring the majority back to 4.1V and use. Save the rejects for flash lights.

Is my plan a good one or not, where does it fall flat. The modules are reasonably priced from eBay . And fun to make too.

Basically I want a large capacity Wh. I don’t want a hot rod but I don’t want lag either especially at lower voltages. It doesn’t take many 14’s to make 100

Part charging is only worth while if you can monitor individual cell balance, how are you going to manage that ?

If using a generic BMS the easiest option is to wire up a balance lead externally to the battery pack to use for monitoring, other wise one needs to use a BT BMS with adjustable settings.