Hi everybody ! Looking at some tips on bulding a golf cart battery out of 18650s this is what I would like to do.
1. Build a 48v 100ah battery to give a range of about 50km this is based on 90wh per km at 80% dod.
So my initial calculations and research suggest building 14 packs (3.7vx14) in series to give me 51.8v nominal.
Each pack must produce between 60 and 200A peak and average is about 80A on flat hill.
Looking at 2.6A cells capable of 4C (10A) such as the M26 or close I'm thinking of 40 cells in parallel per pack and an array of 4x10 cells with 2 busbars each with 5A fuse wire to each cell spot welded.
Now I have read that the lugs from each side (+ and -0) must be at opposite ends for best flow of energy
Or can keep them to one side of each parallel pack for securing ?.
I could build different pack configuration but I figured this would be the best for 560 cells also from a balancing point of view I will be using 2x ISDT 8T charger each on 7s of the pack side by side at 30A charge which will feed about 0.75A of charge per battery or about 0.35C on an M26.
Looking for ideas and possible mistakes I'm making in my calculations and also to open up a thread on building your own golf cart batteries.
This pack should replace my 4 Trojans lead acid batteries that weight 160kg for 7.2kwh or more like 3.6kwh since 50% discharge is recommended on lead acids to prolong life. And will only weigh about 25kg for 5.3kwh at 80% dod or 4.2kwh of usable energy !!!
1. Build a 48v 100ah battery to give a range of about 50km this is based on 90wh per km at 80% dod.
So my initial calculations and research suggest building 14 packs (3.7vx14) in series to give me 51.8v nominal.
Each pack must produce between 60 and 200A peak and average is about 80A on flat hill.
Looking at 2.6A cells capable of 4C (10A) such as the M26 or close I'm thinking of 40 cells in parallel per pack and an array of 4x10 cells with 2 busbars each with 5A fuse wire to each cell spot welded.
Now I have read that the lugs from each side (+ and -0) must be at opposite ends for best flow of energy
Or can keep them to one side of each parallel pack for securing ?.
I could build different pack configuration but I figured this would be the best for 560 cells also from a balancing point of view I will be using 2x ISDT 8T charger each on 7s of the pack side by side at 30A charge which will feed about 0.75A of charge per battery or about 0.35C on an M26.
Looking for ideas and possible mistakes I'm making in my calculations and also to open up a thread on building your own golf cart batteries.
This pack should replace my 4 Trojans lead acid batteries that weight 160kg for 7.2kwh or more like 3.6kwh since 50% discharge is recommended on lead acids to prolong life. And will only weigh about 25kg for 5.3kwh at 80% dod or 4.2kwh of usable energy !!!