Recent content by CUDAcores89

Announcement - Looking for casual help with the design, management & upgrading of this forum. Must have knolage of Zenforo and be able to display past work with solid evidence of your abilities. You also need to live in Australia so we can meet in person before comencement of work. Send mail to admin at diypowerwalls dot com.
  1. CUDAcores89

    What To Do With Free Lead-Acid Batteries?

    give them to me? lol. Or bring them into a scrapyard. They'll pay you by the pound.
  2. CUDAcores89

    why do we have status updates?

    why do we have status updates?
  3. CUDAcores89

    Lumpy batteries?

    ANY lithium cell you bring in that has water ingress if any kind I immediately throw away. Humidity + used cells tends to not mix well.
  4. CUDAcores89

    18650 self discharge

    To respend to @Drivee, I don't even bother with 18650 cells below 2000mah. By that point they tend to be on the very end of their lifecycle and have a substantial dropoff in capacity 1-2 years later. There's a reason 2000mah is the threshold for a lot of folks if you're building a larger battery...
  5. CUDAcores89

    [SELLING-US/MI] PRICE DROP 12v/14.8v 30000mah Powerizer PL-9059156-1C PR-CU-R574 Batteryspace Lipo Batteries

    I have 28 of these. This is a copy directly from the eBay listing I have for these batteries. For sale is one Powerizer 12v 14.8v 30000mah PR-CU-R574 Lipo battery. This battery was used for only a few cycles in a prototype environment and is ready for resale. The grey 3-pin connector is a...
  6. CUDAcores89

    Packs for Harvesting (Toronto, Ontario, Canada)

    I hate to burst your bubble, but $1 a pack is what a lot of sellers here are paying for their packs. Nobody's gonna sell packs that cheap as a reseller, especially if it's canadian. I can buy laptop batteries at my recyclers for anywhere from $1-2 a pound, depending on the cell type and...
  7. CUDAcores89

    Value of Ebike batteries

    High drain cells tend to cost a lot more because they are constructed better. I used to pay $1-2 a cell for "proper" ebike cells. You don't want to use crappy old laptop cells for an ebike, I learned the hard way. They heat up like a bitch and die early. Power tool and hoverboard battery packs...
  8. CUDAcores89

    Under discharge 1 cell went low

    As a rule of thumb for pack design, keep your charge and discharge leads connected as far away as possible form eachother. For example if we had a 4S100P square battery pack, you would want to connect the negative lead in the bottom far left corner on the bottom and the positive lead in the far...
  9. CUDAcores89


    Also make sure the discharge rate of the pack is the same or higher than the origonal battery. Working with high power density battery packs is a whole nother can of worms than a powerwall. I would know, I build ebike packs.
  10. CUDAcores89

    Nissan Leaf Packs - Batteryhookup

    I have played with leaf cells a bit, I used them on my ebike once. They have very good charge/discharge and cycle life characteristics. I've run them at 100A no problem before. they are also rated for thousands of cycles. 2000+ is possible with good care. I ended up not using mine because they...
  11. CUDAcores89

    Strange 3.6v cell

    your biggest concern when building a powerwall is that the end State of Charge is identical. In this case, most lithium cells (including the ones you have) have a final voltage of 4.2v. So yes, you cna mix them.
  12. CUDAcores89

    BYD , CATL & Sinopoly , Winston LFE Cells

    The reaosn we don't hear about them so much is because as you have said - they are a small scale cell producer. I havew only ever seen their cells once, and that was from my local scrap yard. Nobody uses them because they are diffucult to find used, and when they are found used they end up...
  13. CUDAcores89

    Battery Voltage drop

    Beware if you do decide to use those IR testers. The resistance between the probes and cell is going to mess with your measurements. I bought one of those awhile ago and created a custom Cell holder using magnets so I could get more reliable readings.
  14. CUDAcores89

    [SELLING] Laptop batteries by the POUND, a Few medical packs - (US only)

    Okay so I haven't been on the forum for a LONG time, but I decided to show up today because I have something new to sell. This time i'm actually gonna answer PMs and close sales unlike the last time (story behind that later). Long story short: I began on this forum (and still am)an ebiker. I...
  15. CUDAcores89

    4s8P x4 packs for ebike pack?

    I always add a fuse to the charge-discharge lead of my ebike pack. Never bothered with cell level fuses since most of my packs are under 200 cells.