I know, I just picked up the first roll of thinner wire I found around. Next time I’ll go thinner for sure.
Is stacking a bit of nickel strip going to help in this case? This is not for connecting the cells between themselves, this is asking just for the ends, like in the 2nd pic where I have the bigger wire soldered to the strip piece which is welded to the cell. Stack another piece of nickel there, solder that as well to the wire?
I don’t know what ur specifically asking but if the weakest link in the main current path is one strip of nickel …yes weld two.
I’m asking only about the ends of the pack (it’s a 12s1p) so where to ends need to connect to the BMS to carry the whole load. This is where I welded a piece of nickel to which I could solder a wire to connect to the BMS. This is where I don’t really understand how I could stack more nickel? Just sandwich a couple more layers and solder the ends to the same wire? Would this help?
U already soldered the wire on so …
If ur only doing 25 amps maybe it’s ok.
It’s alive! 
Ended up welding another piece of nickel on the ends of the pack. It was possible to still solder it to the wire as I could wedge something there to separate the soldering zone from the cell. It’s solid now and I’m sure it’ll handle the current it’s going to need.
Everything else is connected and as crazy as this may sound, it actually powered on. It was the most beautiful green light I’ve seen in a while. Hearing the motors start up was equally glorious.
It’s charging now so no test run… and of course it’s raining outside. I need to find an old boosted v1 manual, I don’t remember the charging routing. When I connected it, it was solid red for a while and then it turned green, but I don’t think it’s fully charged yet.
I also decided for testing and easy access, to add connectors to the pack leads. I’ll see how I hide the wires tomorrow.
*charging routine - I can’t find the edit post button.
Slight change of plans. In hindsight I don’t necessarily need the battery removeable and to make room for those connectors I’d need to raise the whole thing by just enough that the original bolts aren’t long enough. At this point it’s just easier to not mess with creating a spacer and buying bolts, I’ll just solder the wires together and that’s it.
It’s been behaving well, I’ve left the charger connected since yesterday (only during the day while I was in the same room) and it’s all working well. Still raining outside so I’ve been riding in the living room, lol
I even managed to install the boosted app and unexpectedly it connected to the board on the first try. We only have about 400 miles on this board (not all done by me, got it used way back in 2015 or so).
We’ll go for range testing as soon as the weather clears.
This thing is a blast. I have no idea why I waited for so long before doing this. Got a chance to take it out just a quick spin to see if it works.
Didn’t go far, just for about a mile roundtrip around the neighborhood, started with full charge (at least that’s what the app showed) and ended with 77%. Not great for just one mile of riding but it’s very up and down around here so maybe that used up more battery. We’ll see when I go for a full run to see the actual range.
The charger does do something weird, I plugged it in as soon as I got back and it only stayed red for a little while, in about 10-15 mins it already switched to green. Is this how boosted chargers are supposed to work? Or it’s not relevant because I didn’t discharge it enough?
Anyway, now I’m 100% sure I want to build another one with more range and bigger/offroad wheels to go on dirt roads too. With the bunch of A123s leftover, I can probably build a nice pack for that.
Yeah that’s about right. The V1 famously only went about five miles hence the “last mile vehicle” branding. A123 cells have great safety and wear profile but not great energy density.
Im pretty sure this is normal. Iirc, standard range boosteds charge in an hr dead to full, so 10-15 for the upper 25% tracks.
Nice work on the revival! Good to see stuff live on and not in the dump.
In this case it’s probably not advisable to use the leftover A123 cells for a new board build. I’ll open a new topic when that time comes after I’ve given it some thought…
Thank you! I do intend on keeping it working as long as possible. It really is a blast to ride. I snowboard and I get pretty similar vibes when riding the boosted board.
A bit more range would have been nice… I was thinking I could take the board and my wife the bike but 5 miles roundtrip might not be enough. Just thinking out loud for now 
Houston! We have a problem!
I was about to make another update post on how well it’s working after a 5 mile run this evening. I chose a nice flat trail and the plan was to test the full range. I rode a couple miles one way, a couple miles back and then just around the parking lot until the remote showed the last light blinking. It didn’t die on me, I stopped and I powered it off. It was still going strong at that point.
Packed, came home, plugged the charger in and… nothing. No light at all, no blinking, nothing. The charger LED was on, the charger is good. At this point I wasn’t too worried, I just thought something had rattled loose or a wire got disconnected. I took the pack off, opened it up again and started checking things. Surprisingly everything was still solid, everything connected.
Please bear with me while I go through everything I checked:
So why the hell is this thing not powering on? Surely the BMS couldn’t have just died like this. Remember, it worked fine, I powered it off before leaving and I plugged it in as soon as I got home 15 mins later. Also, the cells can’t be the culprit, it shouldn’t even matter if we have cells connected at all… if anything wrong with the cells but the BMS would be fine, it would blink red when the charger is plugged in.
Please, any suggestion is welcome. What else could I try? I was so happy I had this working 
Sad. Still nothing.
Went back and checked all connections again. All cells are at 3.29v, the charger outputs 43v. There are 3 leads going from the charger connection to the BMS board: black, red and blue. Black+Red show 43v and Black+Blue show a little lower, around 42. Assuming this is normal. Voltage is going in the BMS. This is where my skills end, I don’t really know how to diagnose circuit board components if they’re not visibly burnt. I stared at the BMS for a good few mins, nothing.
One crazy scenario does come to mind. With the longer ride, from the vibrations, maybe some tiny piece of metal/solder came loose in the pack case and when I flipped the board over and put it in the car, it fell back down on the BMS and shorted something. I never noticed any such piece when I opened it up though.
I really don’t know what else I could try. I’ll take off the BMS from the cells, maybe try cleaning it with IPA and a plastic brush… thinking out loud…
We should also start planning for alternatives. To be honest I don’t want to deal with Boosted hardware anymore. I could probably find a v1 BMS on ebay but I really don’t want to go that route. I’d gladly spend a bit more and change out the electronics.
Having said that, I will need some guidance from you guys. Considering 12s is fast enough for me and that I’d like to keep the original motors for now, what ESC, remote and BMS should I be looking for? For starters I’d use the same 12s1p cells. I can always make a bigger enclosure and go with 12s2p later.
I don’t mind spending a bit more on better parts so let’s see if we can get a shopping list going.
I’d grab yourself a makerX DV4 – they’re tiny and can handle all the amps you’d need.
Oof, sold out right now. I think they’re rolling out a new version so hopefully that’s in stock soon.
I’ve also got a spare makerX DV6 that I’m selling for $175 shipped, but it’s a bit bigger than the DV4. Might be hard to fit in the enclosure.
@frame is also selling a cheap Unity 
Cool, I see the DV6 measurements, let me see if it would fit.
I’d also need to understand what remote I can use with it and how it would connect.
Oh and what about the motor sensors. With boosted I see 2 leads with 5 wires from each motor. Would I be able to find out the pinout and connect those to the new ESC?
Please treat me a as a complete noob when talking about DIY board parts. I know my way around ESCs, batteries and brushless motors but not from the esk8 world.
What does “cheap Unity” mean?
Any VESC compatible remote will do, the most popular and reliable option being the Hoyt Puck
I’m not sure what connector Boosted motors come with, but you can likely just swap them to the right size JST connector and call it good. Maybe someone else can chime in for this part.
The Focbox Unity is a relatively reliable VESC that’s been around for quite some time. The dude I tagged is selling one for cheap. It’s comparable to a makerX DV4.
Hell, while you’re at it, check these out:
Considering how safe the cells are Id skip the bms and balance externally with simple discharge balancers.
Very interesting. I’ll keep these in mind, if nothing else, for the idea of new enclosure shapes. I’m fine designing my own and I have a large format 3D printer. These would work fine printed in ABS.
Never heard about discharge balancers. I’ll read up. The idea of using a complete BMS would be for me to keep using the same charger and not worry about the battery in day-to-day use.
BTW, this thread is a big inspiration: 3D Printed Boosted Board Killer
I could print the same enclosures easily.
In a final effort I took the BMS off and connected only the charger leads back. Still nothing. We should have had at least the red light come on.
I don’t understand how it just died like this. It was working so well…
Surely it can’t be the charger… it measures 43v just as it says on the label.
I guess we’re going to move forward with the new hardware plan.
It’s somewhat more clear now what VESC I need but I’d still like to look for a BMS option which would play nice with these cells and need to decide on a remote.
