How To Make A Lithium Battery Pack With 18650 Cells | Practical Skills For Makers

In this video I show you how to make your own custom lithium battery pack using the common 18650 lithium cell. I talk about how to connect the cells in series to get the desired voltage you need, and how to connect the cells in parallel to increase the capacity of the battery pack. Then I go over how to arrange them in the plastic spacers, and how to use nickel strip to spot weld the cells together. Finally I talk about using a battery management system (BMS) to add protection and properly balance the cells as you charge them. I wrap the whole battery in a protective insulating layer and shrink wrap.

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[mrhow]

You have to make sure the voltage is all the same before connecting batteries. Surprised he didn't mention something so important!

[HawkImagery]

the beat with the spot welding is a nice touch

[tariqbacchus]

Man watching you spot weld those pink lithium ion cells together was so satisfying to watch!

[michelkotoff-rizzo]

Loved this video. I went to school for electrical engineering and I never made the connection that building this sort of thing was this simple

[mtherr]

When selecting battery cells, AH specification is important but it should be mentioned that continuous discharge current is equally important. Some cells can discharge at 20 amps rate while others will allow discharging at less than 3 amp rate. The current capacity of the nickel strips should also be considered. I also found out that not all BMS will balance batteries. Some are battery controllers that will protect from over discharge or charge and will not do the balance function at the end of the charge. I do like your videos.

[pandaexpresso]

thank you so much for doing the wire management around the bms. underrated step.

[ExplainingTechTips]

Youre not gonna believe me but your channel deserves 10 million subscribers. When people dream of tinkering but dont know what to do or how to do it. Your channel doesnt show up for regular people I dont even know why I found it. What an amazing channel. I remember now I searched what is inside a 18650 battery

[HowTodo]

Wow great tutorial on how to make battery pack from 18650 battery cells. Very professional work.

[chuckraymond]

excellent job, I especially like adding combustion fuel rubber insulation. it will make overloading more exciting

[richardisom]

Cool video, I've seen a few others about building a battery with BMS but your knowledge and background helped explain in more detail.

[forked-lightning]

Great video, first time viewer. I liked your production quality and how you went over the build and emphasized safety when appropriate.

[tedhaas]

Looks great. The only problem with the insulating packaging you installed, is tho it insulates currents well, it also locks in the heat dissipation from each battery, thereby creating a tremendous amount of heat over time, which I'm sure you know how that effects longevity of the cells and changes in voltage output. Instead, I suggest coating the exterior of any exposed nickel plating, soldier joint and exposed wire ends with some non-conductive clear enamel paint, then when completely dry, install it into a non-conductive polymer/plastic electrical box, with a cooling fan on one side and a vent with a dust filter on the other side of the box to allow airflow to cooling the ambient air inside the box and to circulate the cooling air around each battery, then be vented out of the box, to help keep them cool and stable.

[BigCaseadilla]

Just came across your channel while trying to learn how to make my own board for a prototype of a product I want to make. Loving your videos so far!

[stafdehat]

Great video. Re: Affordability, it turns out that those 18650 cells can very often be found in old tool/laptop/etc battery packs, and very often, the pack itself is only bad because 1 of the 18650 cells in that pack is bad (parasitic). In those cases, people will throw away the whole pack, and you can dissect it to recover free, healthy (albeit used) 18650 cells. The downside there is that you need to test all your recovered 18650 cells individually, or suffer increased risk of fire/failure. Another youtube channel, "DIY Powerwall", has information on this.
Also, tip: You can often use a Flir IR camera to identify which cell in your pack is bad, if/when that happens.

[PatHaskell]

Love how people are always posting videos on a project that they have never done before.

[majmaldcinformation]

Thank you very much sir I have learned a lot from your video the spot welding method of nickel stick using 18650 cell is very well explained thank you sir

[Rustic_Farmer]

Love the spot welding to the beat of the music. Excellent stuff.

[awaitingthetrumpetcall]

I have wanted to build my own battery. Thanks for posting.

[Dtr]

I bought one of those exact same battery welders. Works like a charm once you learn how to use it. I would suggest either attaching the two leads together by the heat shrink or printing a bracket to hold them together because it gets really cumbersome with the leads all loose

[craigrmeyer]

Thank you for sharing this. I know this is pretty basic stuff -- no Nobel Prizes here -- but still I appreciate being shown what this looks like in the flesh.