BMS - common port or not?

[Bikes4two]

• Before I commence my next battery build I'm wondering whether to use a common port charge/discharge version or a separate charge port version?
• Apart from maybe the convenience of one vs the other as in reduced number of connections, space, size and so on, are there 'electrical' or other reasons that might sway choice?
• I note that most common port BMS seem not to offer on/off switching but as a tsdz2 ride I need that function due to the odd occasion a power off/on is required whilst riding.

 

[Nealh]

The BeMuchSafer BMS brand I bought is same port and has a switch you just have to look for them, It doesn't though have charge balance just lvc/hvc protection. One can always wire in an active balancer to look after the cell banks.
Bms 10s 36v 15a Temperature | Bms 13s 20a Temperature - Battery Accessories & Charger Accessories - Aliexpress

13s Battery Active Balancer | 12s Lifepo4 Balancer Board - Battery Accessories & Charger Accessories - Aliexpress

10s balancer - Shop Cheap 10s balancer from China 10s balancer Suppliers at Minerals Official Store on Aliexpress.com

 

[Nealh]

For my drinks bottle battery I went to 12s and same port for the smaller BMS footprint and one less thicker wire to bulk out the space. 13s was two cell to many so 12s was a good compromise for wh.

 

[saneagle]

• Before I commence my next battery build I'm wondering whether to use a common port charge/discharge version or a separate charge port version?
• Apart from maybe the convenience of one vs the other as in reduced number of connections, space, size and so on, are there 'electrical' or other reasons that might sway choice?
• I note that most common port BMS seem not to offer on/off switching but as a tsdz2 ride I need that function due to the odd occasion a power off/on is required whilst riding.

Very interesting question. Normally, I'd say get one with a separate charge control MOSFET for safety, but when you want to run batteries in parallel, you can charge them while in parallel with one charger, since the output MOSFETS isolate the cell-pack when any cell reaches maximum. I didn't think of that before. You can't use two chargers while the batteries are in parallel because after the first battery switched off the charging, the second would get double the charge rate.