Steady the battery while helper moves out the car before together lifting the battery away from the car. Pack perched on my recycling bin before disassembly. Unclip fan cable and remove fan after undoing duct retaining bolts (6 via socket, 2 via spanner). Remove 6 retaining screws and lift opaque plastic safety cover away.
When breaking down a lithium-ion battery pack, having the right tools for the job is critical. The tools you use to disassemble a lithium-ion battery pack can be the difference between salvaging a bunch of great cells and starting a fire. 5 pack of flush cut pliers. Perfect for removing the nickel strip that is attached to cells when salvaging.
Start spot welding the new battery pack and get it to resemble as much of this as possible. Carefully separate the old battery from the housing and start peeling away tape. Remember to separate the thermal probe!! If your BMS belongs to the evil ones, have the old and replacement packs charged up to roughly the same level.
Whatever the main battery pack is electrically connected to, remove it. Remove any circuit boards, regulators, lights, wires, or anything else there is, and get it down to the raw battery pack. Step 2: Mask off the area that you are not working on with Kapton tape or any other easily removable adhesive insulator.
First, you need to figure out what's wrong with the pack—either bad cells or a wonky Battery Management System (BMS). If it's the BMS, just swap it out with a new one. The BMS keeps an eye on the battery pack's performance and makes sure everything's working within safe limits. Replace the bad BMS, and your battery pack should be good to go.
Use 12mm socket / extender bars & ratchet to remove the four battery retaining bolts into the chassis. One is hidden beneath the fan duct loosened earlier. Use grabber to remove bolt safely. Example photo below... Remove 10mm bolts at tubular brace near centre of car - re-fit bolts for safe keeping. Leave brace clipped to loom.