Just posting some pics of a homemade 48V 20Ah ebike battery pack. It is a 10P 13S pack with a BMS. I'll heat shrink it eventually. I figured this might be useful to someone that's thinking about building a homemade pack.
All the cell to cell connections were made with 0.15mm x 7mm Pure Nickel...
Just posting some pics of a homemade 48V 20Ah ebike battery pack. The 18650s aren't the best because they are 1C but they were new and got them fairly cheap. I made sure all parallel units had the same number of the different types of 18650s so that all of the parallel units were a close match...
The motor was design to be used at 750 W. It should be able to handle that power rating continuously. However, riding it at anything lower will extend the life of the motor. I try to keep mine under 500W. I plan to ride mine continuously at 500 W once I build a new pack from some Sanyo 18650GA...
I actually haven't had mine for that long and have about 1300 miles on mine. As long as you're not going up ridiculous hills on your high gears and have a good battery, you're going to have a good commute. I sometimes ride hard and the motor is warm but not hot after a one way trip. Below is my...
I also have a BBS02. Since I commute 16 miles (round trip w/out a recharge) with some large hills to the university everyday, I only use the throttle on the way there to prevent breaking a sweat. On the way home, I use the PAS. I general pedal up hills to help the motor and to get up them a...
Edit: I have misread Lowbank's diagram. I thought he only had 0.7mm^2 for the series connections but it's 7mm^2!! That should definitely handle the 40A per line if the desired amperage is 120A from the 12P Sanyo 18650GA cells. According to Nobuo's chart you can get away with only 2mm^2 of copper...
I posted something similar awhile ago. Maybe there's something there that would be helpful to your design.
https://endless-sphere.com/forums/viewtopic.php?f=14&t=75286
Would you at least have a parallel connection on the first set of positive terminals for the first set of parallel cells so that you could attach your positive lead(s)?
If not, how would you connect your positive lead to the pack?
Basics:
Below is a design, suggestion by bikegeek, for...
Gaskets on the positive terminals and insulation between the groups connected in series are always a good idea and planned for the pack. Besides adding a BMS, which of the designs originally posted do you believe would equally balance the stress felt by each cell?
Basics:
Below are four designs for connecting a 10P 13S 18650 pack that will have a 25 amp limit. All the cell to cell connections will be made with .15mm x 8mm Ni Plated Steel. The 5 lead wires (16 - 20 awg) merging into one (10 - 12 awg wire) will be all the same length.
Questions:
-Which of...
I'm attempting to construct a 11P13S triangle battery pack (w/ BMS) out of 18650 Li-ion laptop cells. This will be connected to a 48V 750W BBS02 (25A current limit).
In the diagram above:
-Each number is an 11P unit that will be spot welded together with 8mm X 0.15mm Pure Ni Plate Nickel Strip...