US69 Posted July 19, 2017 Share Posted July 19, 2017 Thats how easy is daisy chaining Your drawing is....overcomplicated... There are NOT 4 lines sitting on chargeport! and i would NOT try to establish something like that... Link to comment Share on other sites More sharing options...
US69 Posted July 19, 2017 Share Posted July 19, 2017 And if you insist on maintenance and taking your pack away... Just do it, that instead of your pack, a cable is used when your pack is not in use: with that (easy) configuration you can just "switch" your pack between chargeport and existing batterie packs...... Link to comment Share on other sites More sharing options...
Chriull Posted July 20, 2017 Share Posted July 20, 2017 @Noillek - it's maybe a little bit late, since you already invested in the batteries, but i fear your project... The MSuper V3s+ is already taking powers beyond it's possibilities and you are introducing some new weak links. The MSuper V3s+ is able to deliver 4,6kW motor output power at 33,8 km/h - test from @EcoDrift published on http://airwheel.ru/test-monokoles-na-dinostende/ Putting this into (a first version) of a motor charateristics diagramm this leads to about 110A flowing at the motor side. At the battery side this current is flowing too, but only while the mosfets conduct - so one gets a lower average current for the batteries. With your planned 8p configuration this means 110A / 8 = 13,75A peak per cell! And it is not guaranteed that the current divides really evenly - there could everytime be on chain of series cells that delivers more. @zlymexhas posted pics of the original cell tabs melting the plastic casing of battery packs (could be some bad spot soldering done or just a too thin tabs choosen) and of a burned out wheel... With your 3,5A Vruzend kit you are asking for desaster - they rely on springs and tabs to keep the contact. Just a bit of corrosion, a weak or broken spring is needed. Most likely you will not notice this for quite some time until the arching gets once strong enough to start a thermal runaway of one cell which will initiate the same to all of the 159 cells... Since you come from the netherlands, there should be enough e-bike shops which should be able to perform a nice spot welding job to your cells! Also @1RadWerkstatt is not out of reach for you - they are specialized in e-bike and EUC battery packs. Imho they are specialized on KS, but maybe they can also sell you some BMS for the GW or even whole profesionally made packs! 10 hours ago, Noillek said: I did a drawing of what my plan was... but just found out that the GX16 4pin can only handle 5 amps... drawing is still valid but need to change the connectors to XT30 for charging and XT60 for power output to the pcb. i still want to remove the battery pack to upgrade and or maintenance. Thanks That should be a normal paralleling of the battery packs - since we do not know by know what kind of protection the new GW packs have and what the extra wires between the packs and the motherboard are for, it could be that you mess this system up (your battery pack shorts maybe some "intelligence/protection" out by connecting the charge and the discharge side) 10 hours ago, KingSong69 said: And if you insist on maintenance and taking your pack away... Just do it, that instead of your pack, a cable is used when your pack is not in use: with that (easy) configuration you can just "switch" your pack between chargeport and existing batterie packs...... This is the "daisy chaining" - the advantage here is, that it will not mess any of this extra "intelligence/protection" circuits of the original packs. The disadvantage is, that the partial motor drive current flows from this pack over the charge side of the other two packs to the motherboard. The charge protection circuits are normally not designed to take this currents. Also if GW has a reverse protection diode at the charge side of their BMS (GW did not have these at their older models - do they now?) these would likely be overpowered too. Also they lead to some "bad" behaviour like your pack not getting regeneratively charged while braking, etc... Maybe you have good luck and everything works out somehow... i would not dare doing this... Link to comment Share on other sites More sharing options...
Noillek Posted July 20, 2017 Share Posted July 20, 2017 11 hours ago, KingSong69 said: And if you insist on maintenance and taking your pack away... Just do it, that instead of your pack, a cable is used when your pack is not in use: with that (easy) configuration you can just "switch" your pack between chargeport and existing batterie packs...... Thank you Kingsong69, i guest that i need to change the charging cables then from the original batteries... since they will need to deal with allot higher current. 18 minutes ago, Chriull said: @Noillek - it's maybe a little bit late, since you already invested in the batteries, but i fear your project... The MSuper V3s+ is already taking powers beyond it's possibilities and you are introducing some new weak links. The MSuper V3s+ is able to deliver 4,6kW motor output power at 33,8 km/h - test from @EcoDrift published on http://airwheel.ru/test-monokoles-na-dinostende/ Putting this into (a first version) of a motor charateristics diagramm this leads to about 110A flowing at the motor side. At the battery side this current is flowing too, but only while the mosfets conduct - so one gets a lower average current for the batteries. With your planned 8p configuration this means 110A / 8 = 13,75A peak per cell! And it is not guaranteed that the current divides really evenly - there could everytime be on chain of series cells that delivers more. @zlymexhas posted pics of the original cell tabs melting the plastic casing of battery packs (could be some bad spot soldering done or just a too thin tabs choosen) and of a burned out wheel... With your 3,5A Vruzend kit you are asking for desaster - they rely on springs and tabs to keep the contact. Just a bit of corrosion, a weak or broken spring is needed. Most likely you will not notice this for quite some time until the arching gets once strong enough to start a thermal runaway of one cell which will initiate the same to all of the 159 cells... Since you come from the netherlands, there should be enough e-bike shops which should be able to perform a nice spot welding job to your cells! Also @1RadWerkstatt is not out of reach for you - they are specialized in e-bike and EUC battery packs. Imho they are specialized on KS, but maybe they can also sell you some BMS for the GW or even whole profesionally made packs! That should be a normal paralleling of the battery packs - since we do not know by know what kind of protection the new GW packs have and what the extra wires between the packs and the motherboard are for, it could be that you mess this system up (your battery pack shorts maybe some "intelligence/protection" out by connecting the charge and the discharge side) This is the "daisy chaining" - the advantage here is, that it will not mess any of this extra "intelligence/protection" circuits of the original packs. The disadvantage is, that the partial motor drive current flows from this pack over the charge side of the other two packs to the motherboard. The charge protection circuits are normally not designed to take this currents. Also if GW has a reverse protection diode at the charge side of their BMS (GW did not have these at their older models - do they now?) these would likely be overpowered too. Also they lead to some "bad" behaviour like your pack not getting regeneratively charged while braking, etc... Maybe you have good luck and everything works out somehow... i would not dare doing this... Thank you Chriull, i guess that there must be a safe way to do this... i will research a bit more and see what can be done safely. The goal is to touch the least possible on the original setup. Link to comment Share on other sites More sharing options...
Noillek Posted July 20, 2017 Share Posted July 20, 2017 Just found an image of the Gotway battery packs... it seems that theres an additional set of wire to balance both battery packs... do you know where are they connected in the BMS? Also i order a BMS from aliexpress and it hasnt been shipped yet... does anyone knows where can i get a good 20S BMS >20A, in europe? Thank you Link to comment Share on other sites More sharing options...
zlymex Posted July 20, 2017 Share Posted July 20, 2017 10 minutes ago, Noillek said: Just found an image of the Gotway battery packs... it seems that theres an additional set of wire to balance both battery packs... do you know where are they connected in the BMS? Those are for charge protect synchronization. When a cell in one pack(the bad pack) is overcharged while the charging is in progress, the pack turn itself off, and tells the other pack to turn off as well by means of those wires. Otherwise the bad pack(although turned off from the charge port) will still be charged thru the output connectors which are connected directly all the time. Link to comment Share on other sites More sharing options...
US69 Posted July 20, 2017 Share Posted July 20, 2017 1 hour ago, zlymex said: theres an additional set of wire to balance both battery packs... do you know where are they connected Thats why i told you not to do it parallel in all my posts! The original packs are kind of communicating with each other and i doubt your 3rd party BmS can do that... Link to comment Share on other sites More sharing options...
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