electric_vehicle_lover Posted December 1, 2015 Share Posted December 1, 2015 Firmware for generic UC -- see here: https://github.com/generic-electric-unicycle/documentation/wiki Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 2, 2015 Author Share Posted December 2, 2015 Ok so today rode until I got the flashing and tilt back warning. Plugged the EU into the charger and after only 10 minutes it started to interchangeably flash red/green/red/green before going stable green after a couple of minutes. Three things come to my mind. 1) My battery is not charging fully 2) My battery is not discharging enough 3) My charger is not working properly This weekend I will check the battery voltages once a few times. Once after fully charged. to check the overall battery output. Once after the first flashing tilt back warning. Anyone else have any suggestions? Still waiting on new battery to arrive. Link to comment Share on other sites More sharing options...
SuperSport Posted December 3, 2015 Share Posted December 3, 2015 52 minutes ago, Jez_Fila said: Anyone else have any suggestions? Still waiting on new battery to arrive. I'm in the same boat on my TG, albeit a slightly different battery, same symptoms. I have not done any more diagnosing, just figured I'd wait for the replacement battery to come, then, if it works, I'd take apart the old one and see if I could fix it by balance charging or something. Didn't want to take apart till new battery arrived, so I didn't make the wheel un-ride-able. One thing I do notice is that it will ride a LONG ways on ONE battery indicator light. Now I'm wondering if it's the Indicator circuit not giving me proper info. Again, when the new battery arrives, there should be some answers. Link to comment Share on other sites More sharing options...
Maxime Posted December 5, 2015 Share Posted December 5, 2015 Hello Jez_Fila, if you have doubts if your shunting creates problems, just try to remove it, it's rather simple ! And make a test if that changes something back. But my opinion is that you have some defective battery elements. Make the test element by element, you will see. Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 7, 2015 Author Share Posted December 7, 2015 Still waiting on that battery from banggood so it may be a little while before I know whats going on. have been keeping a keen eye on charging times and it takes around 15 minutes in average until the charger light goes green. Does anyone know what causes the light to change from red to green. Is its internal to the charger? I took the whole thing apart and made sure there were no loose connectors. Whole I was there I cut out the guards a little to give the wheel more clearance. Link to comment Share on other sites More sharing options...
esaj Posted December 7, 2015 Share Posted December 7, 2015 9 hours ago, Jez_Fila said: have been keeping a keen eye on charging times and it takes around 15 minutes in average until the charger light goes green. Does anyone know what causes the light to change from red to green. Is its internal to the charger? At least on the Firewheel charger, the light goes green once the charging current drops below around 250mA (if I remember correctly). Probably it's similar in other chargers, but the current where the light changes might be different. The charging happens in two phases, constant current (CC) and then constant voltage (CV). First with full current and the charging voltage slowly goes up, until it hits the full voltage and the charging current starts to drop. Once the current has fallen enough (the battery is near full), the light will change from red to green. Graph made from Charge Doctor data while charging 3 * 192Wh batteries from (almost) empty to full with the Firewheel charger: Left-hand scale is for current (100's of milliamperes, so 20 = 2.0 amps) and voltage (single volts, so 60 = 60V). Right-hand scale is for watthours. X-axis is minutes. Around 260 minutes, the full voltage is reached (blue line) and the charging current starts to drop (red line). Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 12, 2015 Author Share Posted December 12, 2015 OK So did some testing today. Turns out that before my tilt back, flashing and beebing starts my battery only gets to 58.4v. I was expecting it closer to 55 than this. Another thing. Full charge on my pack is 61.2v and not 67.4v. No wonder I can only do 1KM before issues start. I think that it would be the battery and the controler. The controller should let me discharge to 55v and my battery should be charging to 67.4v. Anyone else have someting similar? Link to comment Share on other sites More sharing options...
SuperSport Posted December 12, 2015 Share Posted December 12, 2015 Tore mine apart yesterday as BangGood has the new battery on it's way. Cells range from 3.7v to 4.1v. I'm guessing that's enough to mess up the charging? If I remember correctly, the Prius Cells needed to be within 0.1v of each other. I'm trying to figure out how to charge them balanced now. My RC Charger died on my last Prius Update, so I may need to get another. Photos of my 264Wh TG F3 battery. 61.5v on Full Charge. Link to comment Share on other sites More sharing options...
esaj Posted December 12, 2015 Share Posted December 12, 2015 11 hours ago, Jez_Fila said: OK So did some testing today. Turns out that before my tilt back, flashing and beebing starts my battery only gets to 58.4v. I was expecting it closer to 55 than this. Another thing. Full charge on my pack is 61.2v and not 67.4v. No wonder I can only do 1KM before issues start. I think that it would be the battery and the controler. The controller should let me discharge to 55v and my battery should be charging to 67.4v. Anyone else have someting similar? Have you measured how much voltage your charger gives out? I didn't check back on this thread, might have been asked before, and the issue of charger output-voltage has been mentioned on many threads.. It should be pretty much 67.2V (for the "safe" value of 4.20V per cell on 16S-pack), the Firewheel-charger actually gives out and charges up to 67.8V (so 4.2375V per cell), so if it's a tad higher, no reason to be alarmed (as long as the cells are the kind of chemistry which has a tad higher maximum voltage, like 4.25-4.35V), but if it's below that, it will never charge them fully. If the charger gives out full voltage, either the BMS is faulty or you have one or more dead cells. EDIT: One thing to remember is that there's (usually) a (slight) difference between "open circuit"- and "closed circuit"-voltage. Meaning you'll (usually) get a somewhat lower voltage value if you measure the voltage between the battery leads while the battery is supplying power to something vs. the meter alone. To be precise, the meter itself actually also creates a closed circuit (I don't think you can measure a real open circuit, because there's no path for the current to travel), but it's so high resistance that it hardly matters... If I remember right, I could get values as low as 63-64V from the Firewheel when the wheel was turned on, even if the packs were around 67+V when no power was being drawn. Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 13, 2015 Author Share Posted December 13, 2015 5 hours ago, esaj said: Have you measured how much voltage your charger gives out? I didn't check back on this thread, might have been asked before, and the issue of charger output-voltage has been mentioned on many threads.. It should be pretty much 67.2V (for the "safe" value of 4.20V per cell on 16S-pack), the Firewheel-charger actually gives out and charges up to 67.8V (so 4.2375V per cell), so if it's a tad higher, no reason to be alarmed (as long as the cells are the kind of chemistry which has a tad higher maximum voltage, like 4.25-4.35V), but if it's below that, it will never charge them fully. If the charger gives out full voltage, either the BMS is faulty or you have one or more dead cells. EDIT: One thing to remember is that there's (usually) a (slight) difference between "open circuit"- and "closed circuit"-voltage. Meaning you'll (usually) get a somewhat lower voltage value if you measure the voltage between the battery leads while the battery is supplying power to something vs. the meter alone. To be precise, the meter itself actually also creates a closed circuit (I don't think you can measure a real open circuit, because there's no path for the current to travel), but it's so high resistance that it hardly matters... If I remember right, I could get values as low as 63-64V from the Firewheel when the wheel was turned on, even if the packs were around 67+V when no power was being drawn. The Charger gives out just over 68v which should be plenty. When measuring I took measurements off the battery discharge cable while it was not plugged into the motor. When the charger started to flash green/red/green/red I noticed that the voltage on the battery read was different. When it was red it was 62.6 and when the charger light went green it went to 61.3. Ill take all the film off the pack when I get the new one, and check individual cell voltages. If I notice that there is a varience in some cells what can be done? Is it possible to charge the cells directly to balance them? Link to comment Share on other sites More sharing options...
SuperSport Posted December 13, 2015 Share Posted December 13, 2015 3 hours ago, Jez_Fila said: Ill take all the film off the pack when I get the new one, and check individual cell voltages. Please respect and fear it a little when you do. It's really easy to short something when it's open. There's a LOT of Energy there. No Metal Tools around that might bump it, etc... Would not take much to become one of those YouTube Videos we've seen lately... Link to comment Share on other sites More sharing options...
esaj Posted December 13, 2015 Share Posted December 13, 2015 7 hours ago, Jez_Fila said: The Charger gives out just over 68v which should be plenty. When measuring I took measurements off the battery discharge cable while it was not plugged into the motor. When the charger started to flash green/red/green/red I noticed that the voltage on the battery read was different. When it was red it was 62.6 and when the charger light went green it went to 61.3. Ill take all the film off the pack when I get the new one, and check individual cell voltages. If I notice that there is a varience in some cells what can be done? Is it possible to charge the cells directly to balance them? I think the safest way to charge the individual cells would be with a separate charger meant for single cells, although it can probably be done with an adjustable bench power supply too, but I'd be careful trying that (small currents and careful with the voltage). Haven't ever tried that myself (and I don't even have a bench power supply, yet...), but I think some people here in the forums have. 4 hours ago, SuperSport said: Please respect and fear it a little when you do. It's really easy to short something when it's open. There's a LOT of Energy there. No Metal Tools around that might bump it, etc... Would not take much to become one of those YouTube Videos we've seen lately... Yes, especially when you go "around" the BMS directly to the cells, it's important to remember that these are unprotected cells (there's no internal safety circuitry in the cells themselves), and shorting them will cause a very high current to run through. They do have some more like mechanical protections though, meant to kill the cell (disconnect the terminal) or offer a way for pressure to release (instead of exploding ) in case of failure to prevent further damage: Link to comment Share on other sites More sharing options...
Keith Posted December 13, 2015 Share Posted December 13, 2015 Part of the job of the BMS should be to keep the cells balanced (although some may do this just by preventing each individual cell exceeding 4.2V) rather than balancing during charge. There should only be two reasons for individual cells being at significantly different voltages: 1) the BMS is faulty or poorly designed. 2) the cell is failing. Both will only be very temporarily corrected by hand balancing the cells. I.e IMHO risk outweighs return. A brand new pack may well have some cell voltage variance, a few cycles if the BMS is doing its job should correct that unless the cells and pack are poor quality ( usually significantly different capacity between cells.) Please consider that if gas does vent from cells it is Oxygen, which will dramatically lower flashpoint and spontaneous combustion temperatures. That is why when these cells do catch light they burn so well and even dry powder extinguishers won't put them out. Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 14, 2015 Author Share Posted December 14, 2015 All this is making me nervous. Once the new battery arrives i will measure the voltage and fully charge it and measure again. Hopefully the new battery is much better.. I will then take the plastic off the old one to see if I can find the cells that have the issue. If there are some dead or under performing cells, what would be the best thing to do with that battery? It would seem that some of it could be salvaged? Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 15, 2015 Author Share Posted December 15, 2015 Its getting worse:( Today after less than one KM I started to get the beep and tilt back. Its come to the point where its not worth it given I am carrying it more than riding it. I didn't buy this to make my arms pop though... Hoping the battery arrives soon from Banggood. Ordered on the 27/11. Hopefully its not to far away... Link to comment Share on other sites More sharing options...
SuperSport Posted December 15, 2015 Share Posted December 15, 2015 @Jez_Fila That stinks. If I'm not riding my NineBot today (only because it's icy outside), I'll try to start balancing the cells in my old TG F3 battery and see if I can get it to take a charge properly. Then I'll know if it's the BMS or the Cells. I've got a charger for single 18650 cells, so I'll rig up some wire clips to the individual cell. Won't leave unattended so we don't have a burned down house for Christmas. Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 16, 2015 Author Share Posted December 16, 2015 I think I understand why my range on the scooter is shot. Also, why after switching off for a few minutes seems to bring new life to the board. I think that this may be the result of the BMS balancing the batteries. After a ride some of the batteries discharge to the minimum. Its at that point that the BMS would want the balance the charge but it cant do it fast enough while riding so the tilt-back starts and it starts beeping. Give it a few minutes and the batteries have balanced their voltages again and you can ride another few hundred meters. And again and again till all voltages get to a collective 55v. Does this make sense or have i just correlated a bunch of random stuff? Link to comment Share on other sites More sharing options...
Chriull Posted December 17, 2015 Share Posted December 17, 2015 Imho the single cells can only be balanced while the EUC is connected to the charger. What you describe seems that the cells just regenerate by itself during the break. Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 17, 2015 Author Share Posted December 17, 2015 My Battery arrived today. 174w of Samsung power. I unpacked and checked the voltage out of the box. Around 58v. Plugged it in and it's taken quite a while to charge. That's easily the most noticeable thing, as normally charge time in no more than 15 minutes. It looks the goods. EDIT: Well the battery charged to 62.8v before the green light went on. Turned on the EUC and pfft. Flashed for a second, heard a beep and then it turned off!?!? switched back the old battery and it was ok, but as soon as I switched back same thing. So anyone have any suggestions? Link to comment Share on other sites More sharing options...
Chriull Posted December 17, 2015 Share Posted December 17, 2015 The EUC made pffft or you? Maybe a fault in the BMS discharge path?... Hard to say... Would be nice to test the battery pack output - but have no idea what to connect as load... Maybe a couple (62,8/12=5) of high wattage 12V halogen bulbs in serie? And then measure the voltage at the output. If the battery pack holds the voltage i fear it's something with the board. Link to comment Share on other sites More sharing options...
SuperSport Posted December 17, 2015 Share Posted December 17, 2015 5 hours ago, Jez_Fila said: My Battery arrived today. 174w of Samsung power. EDIT: Well the battery charged to 62.8v before the green light went on. Turned on the EUC and pfft. Flashed for a second, heard a beep and then it turned off!?!? That's a bummer! My 264Wh replacement battery is arriving today also. I'll report back after testing. Maybe your Motherboard has been the issue all along? I'm wondering that myself, but in my case, I wanted to get the battery Under Warranty first, because the Motherboard is MUCH cheaper if I want to pick that up next at my expense. I doubt BangGood would be wiling to send that for free too. Link to comment Share on other sites More sharing options...
SuperSport Posted December 17, 2015 Share Posted December 17, 2015 My Battery Arrived. It came in at 64.1v out of the package. I'm charging now, and I can happily report it's showing 4 lights on the wheel before charging. I believe in my case, it was the battery that was the issue. I've adjusted my charger to be exactly 67.2v without a load, so I'll see how that works out. (Follow This Link to See How to Adjust) Have you checked your charger output voltage? As asked above, did your battery actually make a Pfft sound? If so, sounds like something on the BMS or elsewhere Popped. EDIT: Battery took a full charge and I have 4 lights on the Unicycle. Now to test ride! Favorite Part. Went Well. 6 miles and 2 lights left. Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 17, 2015 Author Share Posted December 17, 2015 6 hours ago, Chriull said: The EUC made pffft or you? Haha. I went pfft...lol the battery did Not charge to 67.4 before the green light came on. Maybe leave it charging overnight and see what happens. Now suspecting my charger or controller.... Arhhhhh!!! i'll take some video on the weekend and post it. This is seriously doing my head in. What's weird is that the old battery works fine. Once. Plug I the new one is like the BMS discharge protection kicks in. The light flashes on for a second and it shuts off. I haven't shunted it yet. Probably won't touch it till I get a response from banggood. Why can't stuff just work out of the box for me??? Link to comment Share on other sites More sharing options...
SuperSport Posted December 17, 2015 Share Posted December 17, 2015 1 hour ago, Jez_Fila said: Haha. I went pfft...lol the battery did Not charge to 67.4 before the green light came on. Maybe leave it charging overnight and see what happens. Now suspecting my charger or controller.... Arhhhhh!!! i'll take some video on the weekend and post it. This is seriously doing my head in. What's weird is that the old battery works fine. Once. Plug I the new one is like the BMS discharge protection kicks in. The light flashes on for a second and it shuts off. I haven't shunted it yet. Probably won't touch it till I get a response from banggood. Why can't stuff just work out of the box for me??? From what you are describing, it does sound like the new battery is having issues. There's really no way to plug them backwards, otherwise, I'd suspect that. Have you verified the voltage from your charger, at least for the old battery? Link to comment Share on other sites More sharing options...
Jez_Fila Posted December 17, 2015 Author Share Posted December 17, 2015 3 minutes ago, SuperSport said: From what you are describing, it does sound like the new battery is having issues. There's really no way to plug them backwards, otherwise, I'd suspect that. Have you verified the voltage from your charger, at least for the old battery? Yep. Charger is putting out 68v. My old battery wont charge beyond 61v. This one peaked at 62.8v which is far less than the 67.4 it should have at full charge. What other tests can I run? I am not taking it apart until BG tell me what they want to do about it. Curious if a shunt would help as the behaviour is similar to what happens when it used to have a cut off before i put the shunt into the old battery. Link to comment Share on other sites More sharing options...
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