Hi everyone!! sorry for bother you with this old issue, but i noted that you guys knows a lot about this...i want to upgrade the battery and after reading a lot ...still not sure if my solution it will work....:

i would use 4 x High Capacity 20000mAh 4S 12C Lipo Pack....

my questions are:

1.- are they power enough? (i ask,  because you explained in other thread that maybe dont release the spected power for a 20r oset)

2.- I 've read a lot about built in BMS...this packs doesnt have built in BMS ....it enough with the charger have some kind of BMS ? (for balance charge, voltage protect etc) or you recomend buy something else for battery monitoring?

3.- The electronic panel of the bike (if the bike would have one) supports that upgrade ? assuming that im gonna connect this packs almost the same way like the old lead acid batteries....i have an rc expert friend who will make the serial connection of the packs before i connect to the bike....he will do something like this tutorial....

 

well...thats all...thanks ALOT!!

4S are probably not what you want as they are 14.4V nominal and 16.8V full. I'm assuming you are thinking to run 4 of them in series to get over 48V. At full charge this is 67.2V, and that may harm your bike.  I'm not certain what the OSET controller or throttle could handle, but why chance it running in the wrong voltage range.  The person in that YT video uses 6S which are 22.2V nominal, 25.2V full.  That would be a closer match to OSET spec.  I didn't watch the video, just identifed his Turnigy packs.

All hobby RC chargers will have a balance mode.  Hobby LiPo's have no BMS therefore its all on you to do it right.  You absolutely need to charge RC packs in balance every few charges.  I balance charge EVERY charge.  Also I keep a log book, and at each charge I also check starting balance V across all cells in the pack, note starting total V, and charging duration time so I know which packs are failing. 

You also need to accurately monitor voltage on the bike and know where your safe cut-off is.  This is critical.  You cannot use the throttle light indicators as they will not indicate proper state of charge on RC LiPo's.

If you have a friend who understands RC LiPo safe handling, I would suggest you have him (or her!) give you a complete tutorial on storage, handling and charging of RC packs.  LiPos are really safe when managed appropriately, and can really ruin your day or life when not. If you aren't sure what I mean, search fire proof LiPo charging bags on Amazon and read 1-star reviews.  Theres some nice pictures too. Nothing like having 5' flames shooting up your wall to learn how not to manage LiPo's or why you want a really good charging plan! 😃

 

Edited April 18, 20215 yr by Westcoast
corrected gender ignorance brainfart