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Showing results for tags 'bms'.
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It triggered me too. Here's V11's BMS, showing the array of small resistors near their management ICs: And here's V12's BMS, with its even more distinct array of 24 bleed resistors: It's resistive top-balancing. Evidently, modern Inmotion EUC's include the same type of cell balancing electronics as their competitors. It's "case closed" for me... if you're not convinced, feel free to discuss below
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For future reference, below are my findings from teardown of a Gotway BMS. DISCLAIMER: This BMS was a Gotway design from 2015, originally sold in the MSuper V2. Battery Management Systems from other models and manufacturers vary widely. What can it do? Disconnect the charger ("Charge stop") ... if any cell exceeds 4.25V ("overvoltage protection") ... or if any cell is between 2.0 and 2.80V ("undervoltage protection") Charge Stop can be linked to additional packs, so that a cell problem in one pack can trigger all parallel packs to Charge Stop. Overvoltage protection is a 'latching' behavior-- it does not reset until the charge input voltage is removed. Top-balancing Balance resistors will be connected to any cell that exceeds 4.20V. (Normally this occurs at the very end of a charging event, when the pack is nearly full.) What are its limitations? No overcurrent (short-circuit) protection.* * charging port short-circuit protection was added in newer Gotway BMS, and I confirmed it works in my 84V 2019-build MSX, for example. In this older BMS, overcurrent in the Charger input (e.g.: short at the charge port) will pass through the Charge Stop FET (rated 200 A pulsed) until some part of the circuit is burned open. Typically the 'weak spot' seems to be the PCB traces between the charging leads and the Charge Stop FET. Overcurrent in the pack output (in both older designs and today's products) is not borne by the BMS PCB at all- the high current will flow through the leads and cell straps. Bolted shorts will flow huge amounts of current, until something melts or the cells themselves become destroyed. No thermal protection. No thermostatic fuses nor temperature sensors are present. Vulnerable to corrosion. Corrosion is likely to cause open-circuits in the connections between the pack and the BMS. If this occurs, Balancing and Charge Stop are defeated. The pack may still charge and discharge normally, but cell imbalance will become progressively worse. Unmonitored, over-voltage cells may cause heating and fires during charging. Unmonitored, under-voltage cells may cause heating and fires during use. How does it work? For each cell, a HY2213-BB3A ASIC is used to connect the balance resistance. For each cell, a HY2113-KB5B ASIC is used to detect over- and under-voltage, and drives the Charge Stop trigger signal. (This device can also monitor current, but that function is not used in the Gotway BMS.) Charge Stop is realized by a FQP50N06 FET, which disconnects the negative side of the charger from the pack. (This device has no built-in overload protection.) How are the packs connected? (The packs inspected were from the Gotway MSuper V2 EUC, an 850wh 5p configuration using 3 packs: 16s1p, 16s2p, 16s2p.) According to my diagram below, only one pack is connected to the charger, and therefore Charge Stop is performed at this 'master' pack only. The two 'slave' packs can trigger Charge Stop using the trigger link connection. If any pack drives a positive voltage across these "HV" and "LV" Trigger Link terminals, all packs will disconnect their Charger input. The trigger link wires are redundant- two "HV" and two "LV" leads are used between each pack, but they are electrically the same circuit. This provides fault-tolerance to open-circuit conditions in the wiring. If the trigger link was broken or not connected, Charge Stop would not be possible, and therefore overvoltage and undervoltage protection will be defeated. Discussion Fast-charging: Charging Input wires could be added to the two 'Slave' packs as well, in order to facilitate fast-charging with use of multiple charging connectors. 1C charging for this 5p configuration is about 13 amps, which exceeds the safe ratings of the single GX16 charging connector, but could be achieved easily by 3 charging connectors in parallel. Aggressive fast-charging at 1C or above is not recommended for these packs, because of the lack of thermal monitoring of cells. Under-voltage: In my tests, I was unable to trigger Charge Stop for the cell undervoltage condition. I had some cell groups disconnected from the BMS, and manually applied various voltages to the BMS cell monitor leads using a potentiometer and 9V battery. I did observe the "overdischarge" output of the HY2113 being driven when the voltage falls below 2.8V, but it did not propagate to the Charge Stop FET. I suspect this irregularity was due to the condition of the damaged and corroded pack and BMS that I was testing; I chose not to abuse a healthy pack to create a cell-undervoltage condition. Backstory: A friend had this old MSV2 that would run but would not charge. He reported a previous instance of a short-circuit and arcing when probing the charging port. I opened the packs and discovered the two 'slave' packs were healthy, but the 'master' pack (with charging input) was badly corroded, with entire balance leads rotted away. Cells were badly imbalanced (some 0V). And the copper trace between the charger input and the Charge Stop FET had burned and blown open. Since the other two 'slave' packs were in pristine condition and very well balanced, I was able to salvage the wheel by simply discarding the damaged pack, and moving the charging connector leads to a remaining pack. After this repair, I was able to simulate Charge Stop events by manually applying a voltage between the Trigger Link HV&LV using 9V batteries, and observed charging current being interrupted accordingly. Cheers
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- battery management system
- cell balancing
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A huge shoutout to Bill, AKA @Freestyler, for his help in making my Master Pro the best long range wheel I'll ever own. And you too can have the same capability. But really, don't do any of this unless you are experienced and understand what you're getting yourself into -
Hello everyone. Some who live in warm countries have the problem that if the battery is heated to 45 degrees, then the battery stops charging until it is cooled to 40 degrees. And after the ride, you have to wait a long time to be able to charge the wheel. I changed the firmware and made that the battery can take a charge at temperatures up to 57 degrees (If the battery gets hotter, then you will need to wait until it cools down below 55 degrees). The original firmware version is version 1.1.6 (Many Russian users like this version, not version 1.1.7 or earlier). I also changed the version display to 1.2.6 so that officially the Ninebot application would not offer to update it. I have temporarily discontinued support for my app, but you can flash this firmware using this app "XiaoFlasher m365(Pro/1S/Pro2) - NineFlasher ES-G30". BMS_Zbms1_v1.2.6.zip BMS_Zbms2_v1.2.6.zip
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Hello, there are some rumors about V8/V8F/V8S not having balancing, also heard something about V10 not having it. That looks not plausible to me for V10. About V8 I heard some cases where the range dropped significantly and it was found the cells were not in balance. Mr Wrong Way warns people about it in his videos. So I would be glad if someone could solve this mystery. Is there someone who had teardown their V8 pack and inspected the BMS?
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Interesting, the new 1.1.7 BMS FW claims better/lesser vampire drain, but after leaving my Z10 unridden indoors for 1+ day (42 hours), I'm seeing what translates into .14V drop per day, roughly 1% per day.
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I have an original Ninebot Mini. After the firmware update to v1.4.1, the battery management system got corrupted and does not display anything. It shows v0.0.0 I downgraded my Ninbot app APK to 3.5.1, and it prompts out firmware update available to 1.3.1 but when l start updating, it fails because the BMS can't update as it timeout. V0.0.0 -> v.1.1.3. Anyone knows how to fix this? It's still the original battery, just that it's locked to 10kmh, has a red led light at the back and is very uncomfortable to ride. -
Hi, does anyone knows what specs are the standard bms for the 20s from gotway? I'm looking specifically at the max current rating that I need for an extra battery pack. thank you
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Hey everyone I've been a lurker for a long time around this website picking up what i can for my new love in the EUCs and i picked up a Zipwheel 16" as my first wheel back last year and have used it for about 5 miles daily up until last month when i was involved in a RTC with a speeding motorist i managed to get out the way but i was unable to get the wheel out in time and it was launched 15ft up the road cracking the case open and throwing the battery. I have since tested the wheel and it appears both the motor and the controller by some miracle survived undamaged as the case seems to have withstood the impact although is now in a sorry state and needs replacing, however the battery although worked for the tests didn't seem to fair as well its landing appears to have damaged something on the BMS PCB (Picture) and being that i don't know what its for i haven't dared to try and charge it for my lack of knowledge in batteries and things i've read about them exploding or catching fire and seeing i have my baby girl in the house wouldn't risk it without seeking advice from someone who knows these things. I have since been without my wheel i have ordered a new battery but i would like to either repair the PCB in this battery or replace it as all the cells appear to be completely undamaged. This being the case i searched online for the same PCB so i could just swap them out but have have no luck in finding the board they used even seeing the model number on the front of it (A4-FL16s-DLC) didn't help me to source a replacement i have looked on aliexpress to see if i could find a different board to replace it with but i have no idea which ones would be suitable as i know they have ones for E-Bikes that would be dangerous on the unicycle, unexpected cutoffs and such and was wondering if any of you here may have had something similar or are more techy then myself who may be able to help me in sourcing a cost effective replacement board as i would hate to see these cells wasted Thank you all in advance
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Hoping someone might be able to chime in on what Ninebot/Segway uses for the BMS. I have a es1 with the dual battery setup however I would like to add extra power for range. via craigslist i bought two broken es1 and the battery packs look fine, voltage was putting out 35 on both packs however the 4pin which i thought was balancing leads dont put out anything on the multi-meter. Off the top of my head I was thinking just pop them in parallel and somehow disable regen but... since I dont know the BMS or how to tap into it i held off. open to ideas =) thanks!
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Hi! Before updating my Z10 to BMS v1.1.7, I want to be sure there're no problems. Never touch a running system! Has anyone updated to BMS v1.1.7 so far? Any differences, do you recommend to update? I'm aware of the following topic, but perhaps it's another release? The new version is available since today. Thank you very much!
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Hello, I have recently get a hoverboard for free. The problem is there is no low battery indicator instead when batery is low the board just goes off by bms. I have read about shunt the bms and changing battery but is there something else that i can do it is not problem when board goes of if there is some warning before. Is there some way to adjust batery low warning ? Thank you
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V5f doesn't charge or turn on. With shell removed and tested, battery indicates zero voltage (72v original, 84v charger). On charger connect, registers 24v for 5 seconds, then drops back to zero. Battery, bms, charger or sleep problem? https://youtu.be/JK-phwb74-4 Another Li-po 48V scooter battery registers 24v, when lamp connected flickers on/off at maybe 10 blocks/second. Problem/solution?
