two more working designs

more a re-design than a scratch design, but still had to push the same amount of pixels and solder.  you’ll see these on the market soon, till then here’s the “factory proofs” with some double-check their Q with my A.

hella bright blinky disks.


ultra cool glow sticks,


and sometimes ya just gotta check how good they printed by removing the top screen print to expose the copper traces.  modern SMD parts are sooooo damn tiny in sub-milimeter kinda tiny.




Vintage Brakes

so these are called Warner electric brakes, designed by the guy who designed magnetic speedometers standard in pre-computer automobiles.  clever design, but i think the standard modern setup is in the plans.

here’s the hub off, friction pads inside the hub, and magnetic coil is the ring around the spindle.


closer look at the hub pads,


i assume it works like: give coil juice, it gets torqued by pulling these pads to it and then the doughnut is forced to turn a little bit.  that turn then pushes on the pad ring to engage the hub.  heres a closeup of the tab that sticks out of the coil ring where it can push on the ring on either side (forward or backward same power).


so yeah, i’m back to the wordpress blog thing, which copies automatic to fbook.



more battery lies

ok, these are HP batteries.  one is as expected, full of cells.


but the other has these black cells, ive never seen black cells before?


oh wait, those are not cells, those are hollow plastic spacer tubes?


i guess even the big buys cut corners when they can?

would never tell from the outside that 1/3 of the cells are missing inside?




hollow promises

original apple macbook batteries are a study in density packaging, not a spare cubic in there, all pouch cell and fancy TexasInstruments BQ battery chip.


was going thru some dead batteries, and found one non-original that felt suspiciously lighter than any others.  you don’t own it till you open it, so,


looks all official on the bottom, CE cert and all that, but, what’s missing inside? how about only 1/3 the space is battery cells?


and what kind of cells are these?  look like some sort of tablet battery, really thin, testing one now shows about 2800mah capacity, WAY lower than what the outside says!


yup, even says only 13.87Wh, way less than the 57Wh the outside says!



at least it looks to have a cell balancer, and since it talks to an apple laptop, must have the original TI chip right?


nope, atmel atmega16, might explain the weird responses from the SMC queries….


ebike part 3

last runs blew out the low volt cutoff, so i added a fancy digital VA meter.


here’s the 400 amp shunt added to the pack negative.


and the whole guts on the bench for testing, fancy meter, 400 amp speed controller, 200 amp cutoff solenoid, and even the new throttle control.


fun first, art second, safety third, how about 250 amp inline fuse on the fly?


all tucked back into the battery box plenty of room for the charge balancer board and a beer or two.


and then stick it all back on the bike.


nice blue LED display, unless use an ipad to take the pic…


Amp game too strong

well, i sent the new ebike pack out, as the new charge balance board was doing ok.


so they ran it hard, i mean really hard, charged it up fine, then ran it even harder still, till the smoke came out.  i don’t know if you’ve ever seen lithium battery fires, youtube can show you, these cells have the equivalent of a few dozen laptops together, so the fire hazard was very real.

lucky, it was just the huge cutoff transistors that melted away.  they must have not been fully “on” with my tap to the balancer board, as the fuses did not blow rated 250amps.


gonna be hard to remove them from the heat sink.


never seen inside one of these before.


now i know how the terminals work, can see the rest of them still attached to the PCB.  i think i’ll do a breaker and shunt instead, a smart display and current monitor, and use the big contactor on the bike as the cutoff.

stay tuned…


electric motorcycle battery pack rebuild

so looks like the smoke stayed in.  all new 14x 48v 40Ah lithium cells, and a new charge balancer board.  i couldnt find one that does 250amps, so i put the 50amp board to the charger, and tapped the cuttoff fet gates to the original 250A board to the motor.  way more kick in the pants than i am comfortable on 2  wheels with.  quantya.

sneaky boat from china

these cells are 40Ah each, and supposedly the factory had to custom make them in this size again.  would make a nice pack for a portable TIG welder, but instead i reubuilt this pack for an electric motorcycle.  full testing tomorrow, but for now, it looks like i did it not wrong. :)