DIY battery (18650s)

[Shagnifico]

Just made my first battery out of 18650s. Very simple and cheaper than buying rc batteries. 3.7v 18650 cells cost less than $10 per cell. 18650s are 3.7v Lion batteries that are the size of Double A batteries. I took three 3600mah cells and made a 3s 12v 10,800mah battery. And it's very small, the size of three double A batteries. Total cost was less than $40 bucks. If I were to buy a good pre-made 10,000mah battery that would cost me upwards of $100? Savings aside, the best thing is the size, and I get to determine the shape. So now I got a 3s battery that is 2" x 2.5" and 3/4" thick with 10,000mah for less than $40 and a few minutes labor. Actually that's not completely true, a spot welder is needed so I bought a new one from amazon for $40. I probably could have used my bench top dc power supply but I wasn't sure, so better safe than sorry. I know a lot of you are going to see a thread about diy lithium batteries and pee your pants. "IT'S TOO DANGEROUS!" It's actually pretty simple and straight forward to assemble these batteries. Now that I know what goes into them and how they're assembled I don't think I would trust a manufactured battery over my own diy batteries. Sort of like packing one's own chute. I know the 18650 thing is old news but man both in terms of economy of space and budget this is the way to go imo.

A word of warning, don't buy any 18650s that are advertised as having 4000mah or higher, they are fake. There are some out there advertising 4000, 5000, even 9900mah, anything over 3600 is false.

[Jofaur86]

Hello, or did I misunderstand? or poorly followed? but if you take 3 elements of 3.7 Volts, 3600 Mah in series, you will have 3X 3.7 = 11.1 volts but still 3600 Mah? and not 10800 Mah, for that you have to make 3 times 3 elements in series and then assembled in parallel? unless I didn't understand your explanations

On the other hand, follows completely in agreement with your point of view on this type of battery, can be expensive, less cumbersome, and safe, for spot welding, there are, for those who like to tinker, numbers of tutorials of realizations of this type of device, on youtube and from a microwave transformer

[Shagnifico]

Ahh that’s right I was thinking 3s3p.

[Jofaur86]

it does not matter, everyone can be wrong Have a nice weekend

[Son of a gun-ner]

What you mentioned about batteries not having the advertised Ah, you and/or others looking in may find this old post of mine interesting

AA Battery Comparison Tests. - RC Tank Warfare
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