Search results

Date Relevance Most replies

  1. L

    Good replacement for fried 48V LiFePO4 BMS?

    Well, well. Sixteen cells, and ever one of them (with no load, after a theoretically full charge) is in the range 3.3V to 3.6V... except the top one, connected directly to the thick red wire, which measured 0.2V. So maybe the BMS isn't fried after all. Maybe it's doing its job, preventing ANY...
  2. L

    Good replacement for fried 48V LiFePO4 BMS?

    Not completely familiar, but I have the general idea. Didn't have my camera handy, nor the time, sorry. They look shiny and new, just like all the others, no visible signs of abuse, overheating, desoldering etc. As I said, they weren't hot, just barely warm enough to feel while the others were...
  3. L

    Good replacement for fried 48V LiFePO4 BMS?

    Hmm, that's unimpressive. But I guess it works, mostly. Drawing major currrent thru the thick red cable could conceivably reduce the voltage it shows, if it's got any DC resistance. It shouldn't have, but... :-\ 59.6V is what I recall that showed. Then when the battery was fully charged (or...
  4. L

    Good replacement for fried 48V LiFePO4 BMS?

    Hi dnmun, thanks for replying. No markings on the BMS or speed controller, totally generic except for the Vpower sticker on the BMS. Bike names only to distinguish between the running and non-running one. When the charger is connected and charging, the hubmotor runs (I lifted the front wheel...
  5. L

    Good replacement for fried 48V LiFePO4 BMS?

    A few years ago I put together two ebikes, each with 48V 20AH LiFePO4 batteries, from Chinese kits. The Trek 7500 had a rear 48V 1000W hubmotor, tops out at 29MPH with big fat me on it, I'm happy. The Schwinn Cimarron had a front 48V 1000W hubmotor from a different manufacturer, tops out at...
  6. L

    Connectors for balancing cables on e-bike batts, chargers?

    These look like the ones! Thank you, Rin, Bob, and Jateureka!
  7. L

    Connectors for balancing cables on e-bike batts, chargers?

    Thanks Bob, I tried your suggestion. The search returned 0 results. Tried it with a zero before the 8, and with a letter O before the 8, no connectors. Tried it with three L's and with two L's, still no connectors of any kind, tho I found some interesting coin collections. Can you check...
  8. L

    Connectors for balancing cables on e-bike batts, chargers?

    Does anyone knnow where to get the connectors that are commonly found on the ribbon cables for e-bike batteries and chargers? Not the heavier 14ga or 12ga wires that carry the main drive current from the batteries. I'm talking about the ribbon cables that are used for cell balancing by the...
  9. L

    The cheapest way to get speed

    The cheapest way to get speed Two words: GASOLINE ENGINE.
  10. L

    "Lithium" battery explodes in San Diego FedEx warehouse

    Yep, guess I didn't use the names right. But my point stands. I wish the media would correctly identify the kind of battery that went bang. Was it a Lithium Polymer, or LiFePO4, or....?? It would also be nice if they pointed out that certain battery chemistries have more instability than...
  11. L

    "Lithium" battery explodes in San Diego FedEx warehouse

    There was an explosion in a FedEx office this morning (Wednesday, April 14) here in San Diego, maybe four miles from where I live. Apparently a box with some kind of lithium batteries in it, went bang. No one was hurt. First I heard of it was an announcement on the local station (KOGO 600 AM)...
  12. L

    Rode the Trek 7500 Ebike to work today (12 miles)

    This isn't the Trek, but is another 48V 1000W ebike I've put together. Performance is the same, and it actually rides smoother than the Trek. I'll probably sell it. .
  13. L

    Rode the Trek 7500 Ebike to work today (12 miles)

    California law defines two kinds of motorized bikes: Those with a top speed of 20mph, and those with a top speed of 30mph. The 20mph ones don't have many rules. You have to be 16 or older, and you have to wear a helmet when you ride. That's it. The 30mph ones (like mine) have more rules. You...
  14. L

    Rode the Trek 7500 Ebike to work today (12 miles)

    Whizzed all the way here nicely, except for the rear rack pack falling off due to my clumsiness at bungeeing it on. 48V, 1000W rear hubmotor, 20Ah two-piece LiFePO4 battery, top speed 30mph on level ground. Registered with Calif DMV, and even has its own cute little moped plate! At one point...
  15. L

    America’s Top 50 Bike-Friendly Cities - Link to Article

    This sounds like they are saying, they found lots of bike-friendly cities in California, but didn't like how lopsided that made the map look. So they took some cities in other states that weren't so bike-friendly, and called them "friendly" anyway, and put them on the map. And they took some...
  16. L

    Trek 7500 conversion, with split battery

    Good idea, dogman, thanks!
  17. L

    LiPo in a Backpack-- Can I make it Safe??

    I'm not a very good off-road rider. My few attempts, when it came to going up a fairly steep, rocky hill, ended up with me going one way while the bike went skittering down the hill another way. Since then, I've pretty much confined my riding to flat areas, mostly paved roads. This is probably...
  18. L

    Trek 7500 conversion, with split battery

    Another nice thing about that kickstand is that it's sturdy, and very adjustable. And when it's down (or up) it's possible to turn the pedals forward or backward, thru their entire 360-degree sweep without hitting anything, unlike the standard one-leg kickstand found on nearly all bicycles. :D...
  19. L

    Trek 7500 conversion, with split battery

    Some pics of the project. I ordered a 48V 20Ah battery from Vpower.hk to be made in two pieces, so I could mount it as shown. They basically made up two 24V 20Ah batteries and wired them in series, with BMS taps as appropriate and a 48V BMS and charger. Works great so far. Bike is somewhat...
  20. L

    Thumb Throttle Upgrade?

    The two thumb throttles I have - one from daoji666 in China, and one from TheLAShop in California (who gets them from China) - are fine. Neither has ever stuck in any unexpected position.
  21. L

    Headway Battery Rust Issue

    I'm in San Diego also, and am very interested in possible rust issues with these Headway cells. Deardancer3, dry environments usually prevent rust pretty well, might explain your lack of rust. Florida is more humid. But now that we've been having some moisture in the last few months, your cells...
  22. L

    How much electric cost to ride an Ebike?

    That's pretty consistent with what I found here. One KWh costs around 19 cents, and it took me 0.89 KWh to charge the battery after the 22 mile ride and BMS cutout. Yep, electricity is a little more expensive here, they ration you and if you exceed the ration, they sock it to you. But...
  23. L

    How much electric cost to ride an Ebike?

    I just tried to figure out how much electricity it takes, and what that electricity costs, to ride an Ebike. Came out with a VERY low figure, which I'm not sure is right. I rode the Trek 7500 Ebike 22 miles. Some flat, some hills, moderate-to-high speeds (15 to 28 MPH). The WattsUp meter said I...
  24. L

    Can I solder directly to Headway 38120 cells?

    I've been told that soldering directly to a LiFePO4 cell isn't nearly as injurious to the cell, as soldering to a NiMH cell. But I'm not sure I'd want to trust such an unsupported word. I'd like to hear from people who have actually done it, good or bad.
  25. L

    Can I solder directly to Headway 38120 cells?

    I've seen Headway 38120 LiFePO4 cells (10Ah) that have screw terminals, and other Headway 38120s that appear to have no terminals at all. I know that some cells have flat tabs spot-welded on. But I can't spot-weld! Does anyone know if it's possible to solder some flat tabs directly onto these...
Back
Top