I haven't bought lithium cells from him, but if you want to DYI build your own custom battery,
Tumich has been selling 18650 cells for a while and there seems to be a lot of good feedback from ES members. Here is the thread (note that the first post is frequently updated/edited by Tumich so you can have an idea of cells available at the moment) : https://endless-sphere.com/forums/viewtopic.php?f=31&t=61608&hilit=tumich
Read carefully to get the details. Cells are pulled from new but defective pack most of the time. Unwelded cells can have spowelding residual marks on them. The prices seem really hard to beat but you might want to check if you'll have to pay additionnal fees in your country if you go that route (shipping, custom, taxes, etc...). Tumich might be able to answer your questions is you PM him. I doesn't cost anything to ask ! You'll also have to learn about building a battery if you choose that route. There are plenty of threads on that subject on ES. But remember to use caution and judgment if you plan on building a battery.... shorting something on a lithium battery can cause a fire and even severe burns. You might also want to lean about BMS, chargers, spotwelding, conductive properties of metals, etc.
One advice I can give is :
don't precipitate yourself in buying any battery! Don't be impulsive in your buy ! Take your time ! Analyse data... You have to learn about eBike batteries to make a wise choice or this could be a huge disapointement. Lithium batteries are expensive and some sellers (eBay, unknown sellers on aliexpress, sketchy websites displaying "too good to be true" prices, etc) might take advantage of that and sell you crap. Make sure you know what
kind of cells constitute the battery pack you'll buy. Make sure these cells are
genuine (lots of fake used laptop cells rewraps). Make sure you get a battery that
has enough of these genuine quality cells to comfortably provide the amps your controller will suck and dump into the motor and that the Wh (or Ah) rating of the battery suits your range needs (of course, make sure voltage is right too). Finally, shop for best prices, but remember : if prices seems to good to be true, it probably is... This requires experience and judgment... So if you're not sure, ask ES members, they can help you confirm that what you are looking at is a great deal or a likely fail. As for this 50Ah battery on eBay you're considering, I would personally gladly pass my turn and NOT buy this.
If you want ready to use battery packs (already built and BMS protected) , than I'd also think that reputable ebike sellers like
lunacycle.com,
em3ev.com,
ebikes.ca, etc., would be good places to look for. But still, make sure you know what cells you battery will be made of. And also make sure the
number of cells in the pack (
S and P : series number for voltage, P : parallel number for capacity (Ah) and amp-rating (A)) is enough to suit your need. Sony VTC4 cells can sustain up to 30A load per cell (albeight at a high temp that could be a detrimental for cycle life) while NCR18650B cells were only designed to sustain a mere 5A load per cells (pretty lame IMHO).Time to read the Battery technology thread on ES for more info.
Declaration of conflict of interest : I have to say, I'd really like to have the opportunity to buy that Lunacycle BBSHD
Ludacriss 50A-controller as a separate part from Eric
. (https://electricbike-blog.com/2017/01/02/too-much-is-never-enough-reprogram-your-50-amp-luna-ludacris-bbshd-controller-to-run-at-60-amps/) I did mention
Lunacycle in this post, among other "advertised" sellers here in this post... Although I have bought some BBSHD parts from LunaCycle, I haven't bought battery packs or lithium cells from them yet (I'm in Canada). Nonetheless, I do believe they provide
guenuine 18650 lithium cells for sell. I do not know how their pack are assembled though, as I have never laid my hands on any of them, but they seem to get good reviews in general. I would tend to buy their battery pack (especially those big ones -- like those high Ah triangle packs -- if built with quality 30Q, HG2 or 25R cells). I would personally trust their business, but once again, this is me. I suggest you read, gather knowledge and judge for yourself.
