bottle battery 36V 9Ah for standard bicycle bottle holder

thingiverse

This is my try to make a sleeper e-bike with bottle like battery. I used Keyde (from Alibaba server) motor in rear hub with built in controller, so very light, very simple and clean wiring. Batteries need to be high current like HG2 or VTC6, max current of the motor in my case is 13A at 36V. You may try some 3500mAh with high current, but I wanted higher power reserve. Battery configuration is 10S3P. I tried my best to explain how it is wired with the drawing. 1S to 9S are easy to understand, the last 10s is different it is vertically oriented and connected with wires. I first created connected each floor separatelly and then soldered (later spot welded) them together they may sit on each other without insulation they are always in series, so no problem. Next step was green connections to wire all 10s in series. Be very concentraded and carefull when stacking the floors, watch the rotation, best way mark visibly the series number on the cells. Next is connecting the wires from BMS, again very carefully check polarity, voltage, work slowly it is quite stressing. Prepare for worst case (fire). the batteries are capable of 60-90 A, the ballance lead can glow instantly if wired incorrectly. cover hot parts with tape. next I used hot glue to fix the flowing ballance cables. than I put some textile tape on the bottom of the pack to give it make softer contact with the bottle. Now is the time to insert into the tube. I highly recommend to make a strong string loop arround the two middle batteries from the bottom through the two openings all the way to the top. It will help to pull the entire stack out if needed. When you try to pull on the wires it will dissasemble between the floors and it is painful to repair. I tested couple times. So you want to have something to pull from the bottom - hence the string. when installed + and - wires connected to BMS and XT60 I covered all visible contacts with textile tape again and that is basically it. The lock for the top is not very strong, so I use tape arround. The spacers in picture are from first iterations, I know ugly, not convincing.:-) I will add the code for tiny85 later, you have to adjust a little for your needs to meassure correctly. Battery electronics consists of battery level indicator (optional) arduino tiny85 and 8 RGB led circle and BMS from aliexpress with integrated balancer. BMS: https://www.aliexpress.com/item/4000298032624.html?spm=a2g0s.9042311.0.0.7bd24c4dzH62Wa RGB LED https://www.aliexpress.com/item/32787336145.html?spm=a2g0s.9042311.0.0.27424c4dikZsk4 tiny85 https://www.aliexpress.com/item/32891293434.html?spm=a2g0s.9042311.0.0.27424c4dqdNHwD Battery used Liitokala HG2 https://www.aliexpress.com/item/4000794648060.html?spm=a2g0s.9042311.0.0.27424c4dlW648v