I have used 26650’s before in 2 builds, and the 6mm difference is easy to compensate for. [https://www.ebay.com.au/itm/26650-Lithium-LED-Torch-Battery-Olight-Batteries-26650/254015170925](http://cheap 26650 on eBay Aus) they are 26mm wide (1.02362 Inches in old timey measurements)
Considering the fact that no continual amperage output rating is seen in the product, I would be wary about purchasing anything like this to build a battery pack. 30q cells are recommended for this purpose because of their PROVEN reliability for build battery packs.
I have take a punt and ordered 36 about $120US for a 12S3P 12000Mah pack worst case i have seen in 26650 is 10A constant 20A Burst I can work with 30A/60A my other 26 pack 12S2P 10000 is 100A. Never gets near that. I have seen these advertised local as 20Amp constant this is likely china factory rating. Its a cheap pack and current is too low i will use it as a portable powerwall with 240 volt inverter. Will update when they arrive.
They arrived they are actually 4500Mah not 4000Mah will capacity test tonight, looks like they built in cell protection. thay are a bit longer than a normal 26650 due to the cell protection, I am going to take the wrap off and see if its easy to remove.
Capacity test still not finished so capacity looks legit not bad for a cell selling $2.30US. 12sx3p (13500Mah) built this weekend double layer ofset to minimise height. Battery will be for new elofty DD build the 54mm deep eskating.eu enclosure will be perfect, will not be able to use a drop deck
Capacity test complete
You need to do a amperage test. Without knowing for sure what they are rated for, you will have a fire.
They could be made with extremely cheap lithium substrate that has decent capacity but dangerously low ampacity.
I have a voltage and current meter i will connect 4 to my 12V inverter 240 Volt inverter see how much current they will do before they heat up too much. These were made for olight torches and these some of these can drink some major amps, i am still thinking 10A with 20A burst for each cell. The surface area of 26650 mean they put out more current then the same chemistry in 18650.my litokala 26650 i have seen my pack do close to 80 amps in 2P. I have some 38120 chinese cells (Headway) that claim to be 180 Amp each and they will max out my 1200watt inverter. But i will be stuffed if i know how to fit 12 in a esk8. My first build I used LG HG2 from ebay that ended up being fake luckily I had then in plastic holders that melted breaking the circuit likely saving my first esk8 from a fire.
Current Test last night my rig got to 18 amps per cell before voltage dropped to zero, on investigation one of the protection boards of one of the cells died. repeated the test with 4 new cells and reached 22AMP the limit of my inverter, cells were very warm but not like sanyo cells get. but no more dead cells. Luckily the protection board was easy to remove, cell just needs a rewrap and now working fine. I intend to remove all the boards and limit the current draw to 15amps per cell. I dont recommend these for first time builders. best bet is [https://ru.nkon.nl/rechargeable/18650-size/samsung-inr-18650-30q-3000mah.html](http://Samsung 30Q)
Opted for 10S3P 12S was just too large for my enclosure. Build is delayed due to only having 12S bms’s so I ordered one from Dickyho who normally only takes 10 days to land parts. All cells have been stripped of protection, rewrapped, capacity and resistance tested and sorted into optimum P groups.