18650 cell pairs battery holder for DIY powerwalls

thingiverse

This is a battery holder for 2 rows of pairs of 18650 cells from recycled laptop batteries. It's used to create a parallel block for a small DIY powerwall. The "bus bar" slot accepts a 7mm x 5mm wide nickel strip or a 6mm² twisted copper cable, usually harvested from a main power cable. Print two per block; I printed one in red and the other in black. So if you want a 24v pack, you'll need 14 of these in total. The early design had a 1 layer skirt to reduce warping on my little Printrbot Jr with an unheated bed. Now I've added a version (v8c) with no skirt and enlarged it by 1% for easier cell fitting. May 2018 additions: I added 2x9, 2x12, and a 2x14 versions for those with larger 3D printers; I'm upgrading to one that can do 300mm wide. June 2018 additions: I added the clip-on small voltmeter holder, the doodad for adding sockets at the bottom end, and the DIN rail mount (only works with the 2x6 small blocks). More details on this project are available at http://www.myonlinediary.com/index.php/Energy/PowerWall. It was designed in Tinkercad: https://www.tinkercad.com/things/lft19zWDf7f and https://www.tinkercad.com/things/2KDykjNCrLk-18650-pairs-battery-holder-2x9-2x12-and-2x14-v9-no-skirt.