Looking inside a Boosted Board
- Thread starter agraham
- Start date
SteveS said:
Motors are not limited by cell count, 6s is just a suggestion, based on common model weights and airplane propellers thrust and power usage.
If the electrical RPM is ok and the rpm/load has reasonable efficiency, you can use any voltage. If you're not setting any land speed record's The motor should be awesome at 12s.
Hi Skdoo
Could you let us know the gauge of the red and black wires connecting to the battery box?
I often need to travel with my board but many airlines no longer accept electric skateboards as either carry-on or checked in baggage. The only way around this I can think of is to make the battery box removable so I can check in the board without any batteries in it.
I plan to add connectors to the 4 wires in the battery box so I can easily disconnect and detach it for traveling. Would be great to know the gauge of the wires so I can get the appropriate connectors.
Thanks!
Hash
Could you let us know the gauge of the red and black wires connecting to the battery box?
I often need to travel with my board but many airlines no longer accept electric skateboards as either carry-on or checked in baggage. The only way around this I can think of is to make the battery box removable so I can check in the board without any batteries in it.
I plan to add connectors to the 4 wires in the battery box so I can easily disconnect and detach it for traveling. Would be great to know the gauge of the wires so I can get the appropriate connectors.
Thanks!
Hash
I want carry my board on a flight too, but wouldn't that change anything? They don't let you take the spare battery pack then?
for connectors XT60 or XT90 are my favorites, and they should be both fine for 10&12awg what I ASSUME they are using.
for connectors XT60 or XT90 are my favorites, and they should be both fine for 10&12awg what I ASSUME they are using.
I'm pretty sure tossing the battery pack in carry-on luggage will work fine. There's no prohibition against carrying batteries in carry-on baggage, and as it isn't a full skateboard the airline will not notice at check-in time. The only hurdle to clear then will be security and since the Boosted battery pack is pretty small, well protected, and within the limits for batteries in carry-on baggage, I think that shouldn't be a problem.
Another idea is to ship the battery separately by courier. With an Epic board with detachable battery I tried this (because the battery was IMO too big to sail through security in carry-on baggage) but DHL in Australia refused to send it, although their rules do say that they can ship lithium batteries up to about 160Wh. Might have better luck with other couriers in other locations, and with the Boosted battery as it is under 100Wh.
I'll probably go with XT150 connectors for the power wires. I think these will fit in the grooves where the wires sit. I tried fitting some automotive 22-18 AWG bullet connectors in the space and they fit fine. The XT150s seem to be of a similar size. And I think 2-pin JST connectors should work fine for the 2 serial wires. Have ordered 'em all from Amazon, will have to wait a week till I receive them forwarded from the US.
Update (25/4): I got the XT150 connectors. They are way too big for the space under the battery. The power wires are 12AWG, says so right on them. I think 12AWG bullet connectors for the power and a JST connector for the serial should work OK. These are also a bit too big to fit completely in the space, but if I make some small depressions in the board at the point where the connectors will be then they should fit fine. Now I'm just super nervous about cutting the wires to put the connectors in!
Another idea is to ship the battery separately by courier. With an Epic board with detachable battery I tried this (because the battery was IMO too big to sail through security in carry-on baggage) but DHL in Australia refused to send it, although their rules do say that they can ship lithium batteries up to about 160Wh. Might have better luck with other couriers in other locations, and with the Boosted battery as it is under 100Wh.
I'll probably go with XT150 connectors for the power wires. I think these will fit in the grooves where the wires sit. I tried fitting some automotive 22-18 AWG bullet connectors in the space and they fit fine. The XT150s seem to be of a similar size. And I think 2-pin JST connectors should work fine for the 2 serial wires. Have ordered 'em all from Amazon, will have to wait a week till I receive them forwarded from the US.
Update (25/4): I got the XT150 connectors. They are way too big for the space under the battery. The power wires are 12AWG, says so right on them. I think 12AWG bullet connectors for the power and a JST connector for the serial should work OK. These are also a bit too big to fit completely in the space, but if I make some small depressions in the board at the point where the connectors will be then they should fit fine. Now I'm just super nervous about cutting the wires to put the connectors in!
Depending on what you mean, and if there is no current limiting built into the charge port, that might be a bad idea.
If you mean hooking an external battery directly to the internal battery, then if there is a significant difference in voltage between them, you'll probably get quite an arc, and contacts will weld together (or a plasma flare will vaporize teh contacts and deposit the incandescent remains on your hands and face).
If the contacts remain connected (welded together) then if current flow continues (presuming no BMS to stop it, and/or presuming the BMS itself isn't damaged or destroyed by the initial current surge), there might be enough current flow to heat the wires enough to melt or even set them on fire.
If the cells themselves are not designed for that high a charging current (for the lower-voltage one, being charged) or discharging current (for the higher-voltage one, being discharged), there may be permanent damage to them, too, or even a fire if they heat up enough.
If you mean hooking an external battery directly to the internal battery, then if there is a significant difference in voltage between them, you'll probably get quite an arc, and contacts will weld together (or a plasma flare will vaporize teh contacts and deposit the incandescent remains on your hands and face).
If the contacts remain connected (welded together) then if current flow continues (presuming no BMS to stop it, and/or presuming the BMS itself isn't damaged or destroyed by the initial current surge), there might be enough current flow to heat the wires enough to melt or even set them on fire.
If the cells themselves are not designed for that high a charging current (for the lower-voltage one, being charged) or discharging current (for the higher-voltage one, being discharged), there may be permanent damage to them, too, or even a fire if they heat up enough.
No, BMSes generally do not have current limiting; except for those that shutdown the output when too much current is drawn. Some might also shutdown the input when current flow is too high, but I expect most have no shunt on the input (charging) port, only the output, so have no way to even detect this.
If yours does, then what would probably happen is the BMS would immediately shut down, and charging would not occur. Or it would shut down, then if it has a timer it would recover and restart, then shutdown, restart, etc., rather like the "hiccup mode" power supplies (PSUs) do.
If it does not, then if the voltage difference is high enough and the cells and wiring have low enough resistance, current can be high enough to cause significant heating, perhaps enough to cause melted wiring, fires from shorts if wires touch after insulation melts, cell overheating/damage/fires, etc. Or the charging FETs could be heated enough to be damaged, or to desolder themselves from the board, etc.
If you know the resistances (or can test them) you can then calculate what should happen at various voltage differences.
You'd have to test the actual situation to find out what would really happen, but I don't recommend that, unless you have money to replace anything that fails, and containment/fire suppression for the worst case results.
If yours does, then what would probably happen is the BMS would immediately shut down, and charging would not occur. Or it would shut down, then if it has a timer it would recover and restart, then shutdown, restart, etc., rather like the "hiccup mode" power supplies (PSUs) do.
If it does not, then if the voltage difference is high enough and the cells and wiring have low enough resistance, current can be high enough to cause significant heating, perhaps enough to cause melted wiring, fires from shorts if wires touch after insulation melts, cell overheating/damage/fires, etc. Or the charging FETs could be heated enough to be damaged, or to desolder themselves from the board, etc.
If you know the resistances (or can test them) you can then calculate what should happen at various voltage differences.
You'd have to test the actual situation to find out what would really happen, but I don't recommend that, unless you have money to replace anything that fails, and containment/fire suppression for the worst case results.