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    Max safe Voltage Difference when connecting two Batteries in parallel

    Calculating the flow would involve knowing the internal resistance of each battery, as well as the resistance of the interconnect. As a guideline, I try to make sure they're within .01V per cell of eachother, so .14V in your case. Then you shouldn't have anything to worry about.
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    Lipo slightly puffy

    A momentary short like that isn't going to have much of an effect on the cells themselves, it's not going to produce a high enough current for a long enough time to overheat anything internal. The actual damage is pretty much what you saw, melted (vaporized) connectors and wires. The fact that...
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    1602 LCD Minimum Wires?

    I remember setting one of these up with a Pi, and IIRC I had to put a resistor across the "Contrast" pads to get it visible. It seemed to be displaying things but they were too dim to be visible. Also you might need to bridge the ground pins on the LCD module, they're all grounds but they...
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    How to Use a Watt Meter

    You'll have to provide more info on the particular meter you're using, there are several types that connect and operate differently.
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    Lithium battery upgrade for mobility scooter

    You're right, 3 pins is enough, I should really sleep one of these nights. The logical next step after improving battery cooling is to make it go much faster.
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    Lithium battery upgrade for mobility scooter

    Given the size of the battery and the very low amount of current you're asking it to handle I don't think you'll have much to worry about even without active cooling. Another way to tackle it might be using a 4 pin connector set for the charger, with 2 of the pins on the scooter side going to...
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    Lithium battery upgrade for mobility scooter

    Generally yes, the BMS will feed power back through the charging connector, some designs actually have them directly connected together. Depending on the rate of charge, you might not need to worry about cooling at all, I'd say 5 or 6A would be totally OK. The simplest solution, that would...
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    High power ebike means none of the rules apply to me

    There is a difference between careless driving and intentional assault with a deadly weapon.
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    What are the best practices for re-configuring BBS02 for use with IGH?

    I would recommend against using pedal assist if you're trying to preserve drivetrain parts. Pedal off the line, and apply throttle once you're moving. I generally pedal until I reach comfortable crank speed, and then ease into the throttle and let the motor take over. I don't use the stock...
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    hi who has experience with canadian police and ebike spec issue?

    OK. Compared to BC, Alberta is kind of a police state.
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    Car2Go closing some cities (Calgary, Denver, Portland, Austin)

    They seem to be doing OK in Vancouver, I see them fairly often inside the city. If I lived in the actual city I'm sure I'd occasionally use one on days where I didn't want to ride, it makes sense for a lot of people in a place where a parking spot can run several hundred dollars a month.
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    Can we ride more than one bike simultaneously?

    A one wheel drive asymmetric trike seems like it would be really terrible in the snow. You'd have serious problems turning toward the sidecar, as it would lift your drive wheel. Bikes with the right tires do just fine on slippery roads, you just need to get good :)
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    hi who has experience with canadian police and ebike spec issue?

    I live in Vancouver and I commute daily on my bike, have for many years. I've never owned a bicycle helmet, and I've never had a ticket. Things might be different in Alberta though, it's kind of a police state.
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    Home-Built Ebike - Swiss Police Suspect Drugs!

    My favorite part is the black duct tape. Just the right amount of tape. Oh and the chain that might actually weigh more than the bike. And yeah I was wondering about Chalo too.
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    Fried Bafang BBS02?

    Which wires did you cut? Shorting the power leads from the battery wouldn't hurt the controller, it's electrically equivalent to disconnecting it (voltage to the controller drops to zero or near it). If somehow you managed to short high voltage battery power to one of the other lower voltage...
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    Does this exist? Regen braking for ebike & trailer.

    Implementing a speed controlled regen would be fairly simple with an Arduino, a regular old magnet/hall type speed sensor, and a controller that supports regen. The most complicated part would be the user interface, assuming you wanted to be able to set the target speed on the fly. If you just...
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    Is this dangerous to do? Need help

    It means the BMS is taking (most likely) the first negative from it's terminal connection to the battery. So the first wire on the cable is 1st cells negative/2nd cells positive. Probably. Check with your DMM first.
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    High power ebike means none of the rules apply to me

    Most of the lane splitting I saw in the video was done properly, as in he was going between occupied lanes. The vehicles in that case have no lane to change into, because there's already a vehicle there. It doesn't look safe at a glance but in reality there's little danger of having a vehicle...
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    upgrading a DYI battery pack

    Should be fine, as long as the existing cells haven't been severely abused in their short life they should still be fairly close in spec to new ones. Make sure the existing cells are at the same voltage (+- .01V maximum variance) as the new ones, to avoid an uncontrolled current current rush...
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    Is this dangerous to do? Need help

    NO! Many shorts! Each one of those negative wires (except the most negative one) is creating a dead short across the set of cells between it and the negative end of the pack. The correct way to do this is by connecting the negative of each set to the positive of the previous one. Since...
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    54.6V charger on a 58.4V lifepo4 pack

    As long as you can verify that it's indeed a 16S LiFePo4 pack, then yes the 58.4V charger is the correct one.
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    What could be the cause of a tripping bms

    You're going to need to get rid of those bad cells somehow. Depending how the packs put together, and since the remaining cell groups are relatively unused it's probably worth replacing them. I'd do all 3 groups that went low just to be sure you're going to have a reliable pack that stays...
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    What could be the cause of a tripping bms

    Well, it could mean that as well but in this context it means that it can't deliver it's rated current anymore, because there's too much resistance through the cell. It's a sign of physical damage to the internal components of the cell. Resistance also means heat, so attempting to pull high...
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    What could be the cause of a tripping bms

    It's also possible that one of the cell groups that went dead is actually toast. It might be able to hold full voltage when you charge it but it sags below LVC under load due to high internal resistance.
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    What could be the cause of a tripping bms

    Sounds like the BMS is hitting it's current limit, or at least what it thinks is it's current limit. What's it supposed to be rated for? It's possible that it has multiple current sensing shunts and one (or more) of them has a bad connection to the PCB, which would cause the overcurrent to be...
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