300cells samsung 20s15p
now you want to put (minimum 1 4s16Ah Lipo to your pack to have more power and speed...to compensate your weak 18650pack)
i struggle now to be honest to you because its YOU....the crazy kid exploring hipower ebike world ^^
be warned if you do anything other then iam writing below.
mixing different cells ...no matter if we talk about chemistry OR age. is not a good idea.
BUT you can do it.
early ebike batteries with 18650 where made of a ugly mix of old laptop cells.
if you plug 3 of your 4S Lipos parallel TO your 18650 pack. N E V E R charge them as a 24s pack.
Internal resistance is worlds apart (!!!)
if you setup the BMS of your Adaptto properly it prevents you burning down your house.
as i dont know any conditions about your cells i can only say that one of them will run away on charging as a 24s pack.
(the weaker ones)
they will hit your PROPERLY setup BMS settings to prevent overcharging. Lets say 4.25v.
Charging will slow down, stop and start again while BMS will try to burn down the away running cells.
BMS is to weak for that.
a full charge may take week(s)
in SHORT: DONT CHARGE it as a Single 24s pack.
(still not sure to submit my post....
- build your wire harness to add your 4s3P Multistar pack (doh, so much work for crap....)
- charge your samsung 20s pack
to 4,0v cell voltage
- charge your Multistar 4s3P
to 50% (3.85v) -> 15,4v
(check every single brick with a voltage checker or multimeter that all cells are same voltage!)
- connect them in SERIES.---->>>> 95,4VOLT now.
- double or tripple check all wire connections. be sure your fuses are on the right place INCL the Multistars now(!)
if you have an unlocked firmware installed on your adaptto it may blow on full throttle on your testride.(Voltage spikes)
if you have an locked firmware, it should work. the controller limits power if voltage is to high.
(i think you will not hit a limit because your weak cell cereal)
go out, enjoy the ride, watch temperatures, and cell voltages.
be sure your setup BMS correct to prevent low voltage on any cell.
face it you probably blow your rare controller.
this is just experimental. think over the work needed.....and risking your stuff for a experiment only.
if everything went well.....charge the multistars as single bricks with a RC charger (i hope you have one)
and your samsung pack as you did all time before experiment.