Attaching a Li battery to a controller

Yves

Pedelecer
Mar 28, 2020
49
7
Hi,

My goal is to try to build my own electric bike from an old womansbike. I bought an electric motor with controller and managed to make it work. Although I started with lead acid batteries, I was happy to achieve this.

My collegue had an electric bike but his middle motor was broken and couldnt be repaired so he gave his bike to me. I was interested because he had a lithium battery with the same voltage as my bike (36V)

My question before i blow something up...: can I just detach his lithium battery and connect the positive and negative to my controller without doing harm to my controller or the Li battery? In the attachment you can see the battery (samsung) with his controller and my motor with my controller (chinese)

I want to use my controller (instead of his) because I dont know the function of all the wires attached to his controller.

Regards
 

Attachments

WheezyRider

Esteemed Pedelecer
Apr 20, 2020
1,632
907
Yes, just make sure that you get them the right way round.
Will the low voltage cut off of the controller designed for lead acid batteries be ok for lithium? I imagine that will be set for about 34 to 35 V so it shouldn't do any harm, but range may be lower than might be expected.
 

vfr400

Esteemed Pedelecer
Jun 12, 2011
9,822
3,985
Basildon
Will the low voltage cut off of the controller designed for lead acid batteries be ok for lithium? I imagine that will be set for about 34 to 35 V so it shouldn't do any harm, but range my be lower than might be expected.
It'll work fine.
 

Yves

Pedelecer
Mar 28, 2020
49
7
Yes, just make sure that you get them the right way round.
You mean that I should attach the battery negative to the controller negative and the battery positive to the contoller positive ? Sry my English is not that good... :p
 

Nealh

Esteemed Pedelecer
Aug 7, 2014
19,990
8,172
60
West Sx RH
You mean that I should attach the battery negative to the controller negative and the battery positive to the contoller positive ? Sry my English is not that good... :p
Yes.