A couple of days ago I said to some people here “Is FlexiBMS still not shipping?” and thought to myself “maybe it’s worth learning electronics and making my own since there is definitely a huge market potential for this”. So I say do it! Just be aware there will soon be competition in the space from Trampa and Freesk8…
I bought it last time when the Flexi BMS was sold for a limited number of 25 pieces. It was a very satisfying product. Compact, charging only, 12s, the long-awaited BMS.
I ordered this time as well.
I am convinced that Flexi BMS is a product that takes DIY ESK8 to the next level.
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Another vote for Flexi, been running the beta I got for a long time and working flawlessly and definitely hope to use it in future builds, was running BMSless before because none of the other comercial alternatives had what I was looking for or I simply didn’t trust them to take care of my battery
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anyone know what’s exactly supposed to go in the address fields? I’m guessing post code is zip code and post office is city and state?
That is correct.
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Ordered!
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Business Finland tuki can help you financially.
I can also recommend the “new” whiteroom treatment they have for winter depression.
Good luck mate!
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ordered!
Ordered
Current orders will be packed and shipped on Monday. Tracking numbers will likely be available during the weekend, but I’ll be bringing all the orders to the postal office on Monday.
Yea, I’m aware there is an 18S BMS coming from VESC and Freesk8. I have looked into them and saw that they are using the LTC6813 battery stack monitor IC, which I was also planning to use on mine concept design for the 6S-18S configuration (most likely will be called “FlexiBMS Lite 18S”). I think I can make a mine distinguished from the competitors by aiming for the compact form factor. Software wise I’m planning on supporting the VESC BMS CAN communication commands/traffic to provide native support.
Doing it all solo is a little intensive, gotta say, especially considering I’m also writing the code for the firmware and handling manufacturing, QC-testing, selling, packing and shipping…
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Hi, the finnish payment options dont work for me and your payment provider keeps denying my credit card. Do you take payments over paypal or Sepa transfer?
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Can someone confirm the bms works good with 10A, or its pushing the termal limits a bit?
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i’m about to buy a 10 amp charger for it as well and was wondering the same. are the wires you sell on your page sufficient for 10a as well?
thanks
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In the desc. it says rated for 10A, so why wouldn’t 10A charging work?
I charged a few times at 10 A, 9 A actually since my 5A chargers only do 4.5 A
Worked fine, I didn’t have access to the temperature but if it got hot, it wasn’t enough to fault, and my BMS is a pretty cramped space with almost no room for ventilation and in a completely sealed enclosure
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Thanks for the info, Im pretty sure we got the flexis from the same batch, the test group right?
I was worried about just that, but if it works fine thats great!
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Yeah, I’m from the beta
Only situation I encountered that it gets hot is balancing, if your pack is really mismatched (more than 100 mV and the Flexi sealed in a enclosure, it will take forever to balance (1+ week), what I did is open it and put a fan blowing directly on it, in one night it balanced
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Yea thats the case with every bms on the market, the 100mA current is even more than average if i remember well.
For example those small daly bms only have 25mA
85mA also think it’s limited to 3 resistors at a time
I think I rember Simon playing with adding more but had issues with temp hitting limits
Edit;
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Currently the static maximum is 5 resistors, but if you’re using the “balTempRatio” then that dynamically changes the allowed resistor count based on the measured BMS temp and max allowed BMS temperature. Aka, say if max temperature is 60 C and balTempRatio is 3, then for every 3 C degrees below 60 C one more balancing resistor is allowed on. This is crude, but works as a good soft limiting, as if the BMS temperature rises, then less resistors are allowed to bleed and if the BMS cools down more resistors can be used and the system reaches a equilibrium at some point.
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