DIY-battery
Intent: This page is created as a guideline whether if assembling/designing your own battery pack is a viable option compared to buying a pre-made battery. Prerequisite software/knowledge (before building a pack)
Ability to draw 2D schematics/diagrams. - you need to do this if you are trying to make a pack with a certain dimension constraint. use of CAD is encouraged.
You know how to use the simulator - You need to know how much current your battery will be drawing.
Ohm's law. Since we are not going into AC power, complex number/angle is not needed.
Ability to read battery cell datasheet. - As the wiki page becomes older, more cell info will be added to the page; but for cells that are not on this wiki/internet in a simplified format, reading datasheet will be necessary. LG M50LT datasheet, from batteryspace, Simplified datasheet of M50LT, courtesy of Batemo.de
You will most likely see terminologies that you've never encountered before, this will be explained along the article.
Equipment requirement
Soldering iron - depending on design, you may not even have to solder anything, but you most likely will for balance wires. Balance wires are used by the Battery Management System (Hereinafter BMS) to read a pack's voltage for charge/discharge/storage.
Battery case - so you don't have corrosion/electrical shorts on your battery. The shape/volume of the case determines how much cell you can fit in the case. You can 3D Print a battery case, and this will be explained further. In general, injection-molded/hardcase plastic battery case (if designed/manufactured well) will be almost always superior to a 3D printed/handmade case. Therefore, the latter cases are for more experimental purpose that market does not provide.
Spot welder - Spot welder of your choice, and something that won't fail after using it for an hour. They are either battery-powered, or supercap-powered. NASA's guideline on spot welding.
Multimeter - used for troubleshooting. Red probe goes on V+, Negative probe goes on V-. Do not mix these up.