I’m putting together my first ebike build out of an old mountain bike. I’m assembling the battery pack from scratch using salvaged 21700 cells. I don’t imagine many people install fuses on their battery packs but given how violent these unprotected cells could be in the face of a short… I would sleep better at night if mine had one. Trouble is, I am having difficulty finding a suitable fuse. The vast majority of fuses I can locate online are automotive/marine/audio fuses usually maxing out at 32V. The pack I plan to build will be 14s lithium ion, and thus tops out at 58.8v. Has anyone else done a battery pack build with fuse? What fuse type/rating did you use? Where did you buy them? What brand?

Any info would be appreciated.

Thanks!!

  • willybe
    link
    fedilink
    English
    arrow-up
    1
    ·
    1 year ago

    That’s not a bad idea. For this kind of amperage you would need a beefy fuse. Assuming a 58v 500w motor something like this.

    https://www.digikey.ca/en/products/detail/littelfuse-inc/089107-5NXWS/5233824

    58v x 7.5a = 435w, so this would blow before full power. A 10a fuse wouldn’t blow until 580w which would probably be a better option.

    The other comments are right, using good components and wires rated for the load, and ensure connections are tight and soldered where possible.