Rawnei Posted February 28, 2023 Author Share Posted February 28, 2023 Went on a small grocery run yesterday, when I got home left the wheel turned off for a while to let it stabilize then checked voltage 131.4v, left it overnight unti today about 24h later it's at 131.1v, so still draining albeit more slowly, at this point I'm wondering if there is a lower limit where it would stop draining and what that limit is. 1 Quote Link to comment Share on other sites More sharing options...
supercurio Posted February 28, 2023 Share Posted February 28, 2023 4 hours ago, Rawnei said: Went on a small grocery run yesterday, when I got home left the wheel turned off for a while to let it stabilize then checked voltage 131.4v, left it overnight unti today about 24h later it's at 131.1v, so still draining albeit more slowly, at this point I'm wondering if there is a lower limit where it would stop draining and what that limit is. It's probably draining the same, only the voltage drop is exaggerated near the top of the voltage/charge curve near 4.2V 1 Quote Link to comment Share on other sites More sharing options...
Wheel Guy Posted March 2, 2023 Share Posted March 2, 2023 On 3/1/2023 at 12:04 AM, supercurio said: It's probably draining the same, only the voltage drop is exaggerated near the top of the voltage/charge curve near 4.2V You're probably right. I took my Master off the charger on Sunday and checked in on it today, it was at 131.6v, down from 134.2v on Sunday. So down 2.6v in 4 days. Interestingly, EUC World still reports 131.6v as 100% battery. 1 Quote Link to comment Share on other sites More sharing options...
Chriull Posted March 2, 2023 Share Posted March 2, 2023 On 2/28/2023 at 7:05 PM, Rawnei said: Went on a small grocery run yesterday, when I got home left the wheel turned off for a while to let it stabilize then checked voltage 131.4v, left it overnight unti today about 24h later it's at 131.1v, so still draining albeit more slowly, at this point I'm wondering if there is a lower limit where it would stop draining and what that limit is. "Once the charge is terminated, the battery voltage begins to drop. This eases the voltage stress. Over time, the open circuit voltage will settle to between 3.70V and 3.90V/cell. Note that a Li-ion battery that has received a fully saturated charge will keep the voltage elevated for a longer than one that has not received a saturation charge." cited from https://batteryuniversity.com/article/bu-409-charging-lithium-ion 1 Quote Link to comment Share on other sites More sharing options...
Rawnei Posted March 2, 2023 Author Share Posted March 2, 2023 7 minutes ago, Chriull said: "Once the charge is terminated, the battery voltage begins to drop. This eases the voltage stress. Over time, the open circuit voltage will settle to between 3.70V and 3.90V/cell. Note that a Li-ion battery that has received a fully saturated charge will keep the voltage elevated for a longer than one that has not received a saturation charge." cited from https://batteryuniversity.com/article/bu-409-charging-lithium-ion I'm not completely following as I have not seen this aggressive draining on any other wheel I ever owned. 🤔 Quote Link to comment Share on other sites More sharing options...
supercurio Posted March 2, 2023 Share Posted March 2, 2023 (edited) @Chriull this voltage drop does not occur when the packs are not connected to the charge board, even when fully charged. That was the first test completed. So that's what makes it a mystery: what does this board do? Is it dissipating the energy somewhere? Is it forcing the packs to balance at all times? It drains a lot faster than S22 Smart BMS that's always running for instance. Edited March 2, 2023 by supercurio 1 Quote Link to comment Share on other sites More sharing options...
Chriull Posted March 2, 2023 Share Posted March 2, 2023 17 minutes ago, Rawnei said: I'm not completely following as I have not seen this aggressive draining on any other wheel I ever owned. 🤔 Sorry - seems i stepped into a topic without reading the prior content 14 minutes ago, supercurio said: @Chriull So that's what makes it a mystery: what does this board do? Is it dissipating the energy somewhere? Is it forcing the packs to balance at all times? Maybe @Rawnei can draw the schematic circuit diagram of the board. Does not look too complicated? 14 minutes ago, supercurio said: It drains a lot faster than S22 Smart BMS that's always running for instance. Bms ic's are designed to monitor cells with a current draw below the cells self discharge. So a nicely designed bms should not notable burden a battery. 1 Quote Link to comment Share on other sites More sharing options...
Popular Post Rawnei Posted March 2, 2023 Author Popular Post Share Posted March 2, 2023 4 minutes ago, Chriull said: Maybe @Rawnei can draw the schematic circuit diagram of the board. Does not look too complicated? 🤔🥴 Is this good enough? 7 Quote Link to comment Share on other sites More sharing options...
mrelwood Posted March 2, 2023 Share Posted March 2, 2023 7 minutes ago, Rawnei said: 🤔🥴 Is this good enough? If the board has just two components, just their values would be of great help. Thanks! Quote Link to comment Share on other sites More sharing options...
Chriull Posted March 2, 2023 Share Posted March 2, 2023 11 minutes ago, Rawnei said: 🤔🥴 Is this good enough? It has a second floor? Are some components on the backside. Just two connectors putting the packs in ?series? do not eat voltage. 1 Quote Link to comment Share on other sites More sharing options...
Rawnei Posted March 2, 2023 Author Share Posted March 2, 2023 (edited) 45 minutes ago, Chriull said: It has a second floor? Are some components on the backside. Just two connectors putting the packs in ?series? do not eat voltage. It's stacked in two layers and have a bunch of components on the lower layer, top layer seems to be only for charge input and fuses for that, lower level has all the logic and it has components on both side. For bottom of below check post below. Edited March 2, 2023 by Rawnei Quote Link to comment Share on other sites More sharing options...
Cerbera Posted March 2, 2023 Share Posted March 2, 2023 (edited) 29 minutes ago, Rawnei said: I don't have photo of bottom from this version I do... If we leave the charger plugged into the wall after charging completes and the light goes green, it does hold its charge then, until disconnected. Edited March 2, 2023 by Cerbera 1 Quote Link to comment Share on other sites More sharing options...
Chriull Posted March 2, 2023 Share Posted March 2, 2023 5 hours ago, Cerbera said: If we leave the charger plugged into the wall after charging completes and the light goes green, it does hold its charge then, until disconnected. As long as the light is green the charger can trickle charge the battery... 5 hours ago, Rawnei said: It's stacked in two layers and have a bunch of components on the lower layer, top layer seems to be only for charge input and fuses for that, lower level has all the logic and it has components on both side. Â 5 hours ago, Cerbera said: I do... To (try to) tell if there is some malfunction/design fault one would need all components labels, values and the datasheets of the active components. And all pin connections. Quote Link to comment Share on other sites More sharing options...
Wheel Guy Posted March 3, 2023 Share Posted March 3, 2023 8 hours ago, Cerbera said: I do... If we leave the charger plugged into the wall after charging completes and the light goes green, it does hold its charge then, until disconnected. I'm not so sure. I've seen it be at 133.6v after 10+ hours of charging. I think it may actually start to drain if you leave it in on green for longer periods of time. Maybe if left for longer, it would start trickle charging and go back up again. Quote Link to comment Share on other sites More sharing options...
Rawnei Posted March 4, 2023 Author Share Posted March 4, 2023 Eh, after tagging Kebye and Fei in the Facebook commentary section of my post again I got this reply from Kebye which to me doesn't make a lot of sense: If I understand him correctly the drain is supposedly because it's balancing the packs but it does this even on perfectly balanced packs. 1 1 Quote Link to comment Share on other sites More sharing options...
Wheel Guy Posted March 4, 2023 Share Posted March 4, 2023 2 hours ago, Rawnei said: Eh, after tagging Kebye and Fei in the Facebook commentary section of my post again I got this reply from Kebye which to me doesn't make a lot of sense: If I understand him correctly the drain is supposedly because it's balancing the packs but it does this even on perfectly balanced packs. If they're all at 0, they're perfectly balanced! 3 Quote Link to comment Share on other sites More sharing options...
Cerbera Posted March 4, 2023 Share Posted March 4, 2023 (edited) 3 hours ago, Rawnei said: which to me doesn't make a lot of sense: This sort of answer from them really isn't good enough. It is vague, diffuse, lacking detail and doesn't address why voltage is lost in balanced packs or where it's going ! They might as well have said 'The sky is blue' for all the help that is ! Very frustrating. I presume if you press them further they just disappear / don't answer ? :/ Edited March 4, 2023 by Cerbera Quote Link to comment Share on other sites More sharing options...
techyiam Posted March 4, 2023 Share Posted March 4, 2023 41 minutes ago, loofv said: If they're all at 0, they're perfectly balanced! You either got four fake battery packs, four packs with broken electrical connections, or a fire hazard, due to defect or extreme abuse, and should not be inside any buildings nor vehicles. Quote Link to comment Share on other sites More sharing options...
Rawnei Posted March 4, 2023 Author Share Posted March 4, 2023 3 hours ago, Cerbera said: This sort of answer from them really isn't good enough. It is vague, diffuse, lacking detail and doesn't address why voltage is lost in balanced packs or where it's going ! They might as well have said 'The sky is blue' for all the help that is ! Very frustrating. I presume if you press them further they just disappear / don't answer ? :/ I just keep asking questions but rarely get any good answers unfortunately. 1 Quote Link to comment Share on other sites More sharing options...
Cerbera Posted March 4, 2023 Share Posted March 4, 2023 4 minutes ago, Rawnei said: I just keep asking questions It's all we can do hey ?! That, and watch our machines like hawks to see what crazy thing they might do next ! 1 Quote Link to comment Share on other sites More sharing options...
Rawnei Posted March 4, 2023 Author Share Posted March 4, 2023 1 minute ago, Cerbera said: It's all we can do hey ?! That, and watch our machines like hawks to see what crazy thing they might do next ! I'm just surprised more people aren't vocal about this, maybe if more people complained they would listen. 🫤 Quote Link to comment Share on other sites More sharing options...
Cerbera Posted March 4, 2023 Share Posted March 4, 2023 (edited) Are you considering going back to the old charge board ? I am, a bit... hard to make an informed decision when there is no information to be had ! Edited March 4, 2023 by Cerbera Quote Link to comment Share on other sites More sharing options...
Rawnei Posted March 4, 2023 Author Share Posted March 4, 2023 58 minutes ago, Cerbera said: Are you considering going back to the old charge board ? I am, a bit... hard to make an informed decision when there is no information to be had ! Well something is supposed to be wrong with those and affect balance negatively, pick your poison. Quote Link to comment Share on other sites More sharing options...
Paradox Posted March 4, 2023 Share Posted March 4, 2023 Do you think that all new wheels with this board installed are discharging in their boxes as they wait to be sold? Could be catastrophic for wheels that go unsold for weeks or months. 1 Quote Link to comment Share on other sites More sharing options...
Rawnei Posted March 4, 2023 Author Share Posted March 4, 2023 (edited) 1 minute ago, Paradox said: Do you think that all new wheels with this board installed are discharging in their boxes as they wait to be sold? Could be catastrophic for wheels that go unsold for weeks or months. Yes but hopefully it stops at some point or you are right it's very bad for them to sit forever. Edited March 4, 2023 by Rawnei Quote Link to comment Share on other sites More sharing options...
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