StreetMeatNYC Posted April 2, 2016 Share Posted April 2, 2016 Can I use this on my 9bot1, I want to use the built in E+ Battery and externally use my E battery http://www.amazon.com/Foxnovo-Parallel-Connector-Extension-Splitter/dp/B017OMELGU/ref=sr_1_1?dd=dgd62TW9IH0rUPq0xzCFHg%2C%2C&ddc_refnmnt=pfod&ie=UTF8&qid=1459561473&sr=8-1&keywords=xt60+splitter&refinements=p_97%3A11292772011 Link to comment Share on other sites More sharing options...
esaj Posted April 2, 2016 Share Posted April 2, 2016 If it's the correct connector (I don't remember if Ninebot used XT60's, probably?), it should be ok. Just make sure to measure the voltages before attaching the batteries in parallel, they need to be as close to the same voltage as possible to prevent a large "balancing" current from occurring between the packs. A large voltage difference can cause huge currents, which could fry your BMS's and even damage the cells (up to a point where they could catch fire / explode). A better solution is to have the packs internally and with charge-wires in parallel too, that way you only need to check the voltages once & then they will keep "level" all the time. Of course that's not an option if there's no space inside the wheel. Link to comment Share on other sites More sharing options...
sbouju Posted April 2, 2016 Share Posted April 2, 2016 I have seen once the internal power connector of a 9Bot1, and yes, it was a XT60 type... Link to comment Share on other sites More sharing options...
StreetMeatNYC Posted April 2, 2016 Author Share Posted April 2, 2016 5 hours ago, esaj said: If it's the correct connector (I don't remember if Ninebot used XT60's, probably?), it should be ok. Just make sure to measure the voltages before attaching the batteries in parallel, they need to be as close to the same voltage as possible to prevent a large "balancing" current from occurring between the packs. A large voltage difference can cause huge currents, which could fry your BMS's and even damage the cells (up to a point where they could catch fire / explode). A better solution is to have the packs internally and with charge-wires in parallel too, that way you only need to check the voltages once & then they will keep "level" all the time. Of course that's not an option if there's no space inside the wheel. Can you explain this in a little more detail, I don't know much about batteries. I just know I have two original Ninebot Batteries. One is 240Wh, the other 320wh, both 55.5V. Would appreciate any detail you can provide about how to check/test proper voltages, etc... My Intent would be to be able to hook up the battery whenever I felt I needed and extra bit of range. Would it be wiser to just build in a cut off switch, so I could toggle between which battery I want manually? Link to comment Share on other sites More sharing options...
esaj Posted April 2, 2016 Share Posted April 2, 2016 11 minutes ago, StreetMeatNYC said: Can you explain this in a little more detail, I don't know much about batteries. I just know I have two original Ninebot Batteries. One is 240Wh, the other 320wh, both 55.5V. Would appreciate any detail you can provide about how to check/test proper voltages, etc... My Intent would be to be able to hook up the battery whenever I felt I needed and extra bit of range. Would it be wiser to just build in a cut off switch, so I could toggle between which battery I want manually? I'm not an expert on batteries or electronics, but I'm fairly sure you don't want to connect two batteries in parallel if there's a large voltage difference. Something like 0.1V or so probably won't do much & the charges even out fast, but the larger the difference, the larger current will flow between the batteries until they "even out" (or something fails). The idea of hooking another battery directly in parallel with another "whenever" would (in my opinion) be bad, unless you can somehow make sure that the voltages are "close enough". Multimeter is a basic tool you could use for that, but carrying one around wouldn't be that practical, and if the voltages are off, you couldn't use the other pack (in parallel) unless you can somehow charge/discharge the packs to similar voltage on-the-go. One way to even out the charges more safely is to use a "bleed resistor" between the packs to limit the current until the voltages are even (probably it needs to be a large power resistor). Switching between internal / external battery would probably work ok, as long as you can be sure that they won't get connected "together". If the battery current runs through the switch, you need to make sure that the switch can handle large enough currents (say, peaks up to 20A or more and constant amperage maybe 5-10A for a longer while? Better check those values a bit closely, I just pulled them out of my hat right now) and voltage (~70V? Not sure how high the voltage can go in regenerative braking). Maybe something like a mosfet- or relay-based switch could work better, if no large enough switch is available? For a more detailed model of what happens when two batteries with different voltages are put in parallel, see here: Although that should be taken with a pinch of salt, it basically models just the first instant when the batteries are connected, after that the voltages will start "moving" (the voltage of the pack being charged goes up and the discharging one(s) go down), so the current & power dissipation changes. Link to comment Share on other sites More sharing options...
sbouju Posted April 2, 2016 Share Posted April 2, 2016 39 minutes ago, StreetMeatNYC said: Can you explain this in a little more detail, I don't know much about batteries. I just know I have two original Ninebot Batteries. One is 240Wh, the other 320wh, both 55.5V. Would appreciate any detail you can provide about how to check/test proper voltages, etc... My Intent would be to be able to hook up the battery whenever I felt I needed and extra bit of range. Would it be wiser to just build in a cut off switch, so I could toggle between which battery I want manually? The main problem is that yo have not enough room in the 9Bot1 to have both inside. Why not simply swap the batteries, when one become too low? I have seen a wheeler doing this, and it juste need two minutes! Link to comment Share on other sites More sharing options...
StreetMeatNYC Posted April 2, 2016 Author Share Posted April 2, 2016 4 hours ago, sbouju said: The main problem is that yo have not enough room in the 9Bot1 to have both inside. Why not simply swap the batteries, when one become too low? I have seen a wheeler doing this, and it juste need two minutes! I really dont want to have to stop and take out my tool and find a spot to be out of the way and open it up. I just want to plug in and go.... Link to comment Share on other sites More sharing options...
esaj Posted April 2, 2016 Share Posted April 2, 2016 1 hour ago, StreetMeatNYC said: I really dont want to have to stop and take out my tool and find a spot to be out of the way and open it up. I just want to plug in and go.... If you choose to go the switch route, get a high-current one, preferably with three positions (on-off-on). I think that should prevent the situation where something like switch vibration could connect the batteries together. Not so sure (I don't know that much about switches ), but something like this could maybe work: http://www.amazon.com/Current-Toggle-Switch-Rubber-Momentary/dp/B006YX51MO It's a "double pole, double throw" (DPDT) -switch that should withstand up to 20A on both sides. Higher amperage rating wouldn't probably hurt though, just to be on the safe side. EDIT: Oh wait, that's a momentary switch, you need one that latches in place. Something like this should suffice (max 250V AC / 25A): http://www.aliexpress.com/item/KN25-203-DPDT-3-Positions-ON-OFF-ON-Locking-Toggle-Switch-Blue-AC250V-25A/32283591199.html? Link to comment Share on other sites More sharing options...
StreetMeatNYC Posted April 2, 2016 Author Share Posted April 2, 2016 How cool would my 9bot be with one of these attached https://www.amazon.com/dp/B00DPX6RR4/ref=cm_sw_r_cp_awd_JQfaxbCAM7H50 Link to comment Share on other sites More sharing options...
esaj Posted April 3, 2016 Share Posted April 3, 2016 9 minutes ago, StreetMeatNYC said: How cool would my 9bot be with one of these attached https://www.amazon.com/dp/B00DPX6RR4/ref=cm_sw_r_cp_awd_JQfaxbCAM7H50 Looks nice otherwise, but it says : Voltage: 6V, 12V, 24V, 32V Don't know if it could then strike through at higher voltages or something? EDIT: Also it has "both"-position, that's just a disaster waiting to happen Link to comment Share on other sites More sharing options...
StreetMeatNYC Posted April 3, 2016 Author Share Posted April 3, 2016 15 minutes ago, esaj said: Looks nice otherwise, but it says : Voltage: 6V, 12V, 24V, 32V Don't know if it could then strike through at higher voltages or something? EDIT: Also it has "both"-position, that's just a disaster waiting to happen Yeah, I was quickly perusing on my phone while I was otherwise indisposed.... so it was a quick and dirty (no pun intended) search. I'll dig in deeper for a legit similar piece that would actually work. Link to comment Share on other sites More sharing options...
Jrkline "Wheel Whisperer" Posted April 3, 2016 Share Posted April 3, 2016 The voltage is not a problem.The amperage is what to be concerned about.The switch you found is rated for 300 amps so you are fine. Link to comment Share on other sites More sharing options...
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