Who needs a bms lol

So I know this is not the most conventional way to charge my battery but I jus can’t deal with this bms crap some I’m hooking up straight to 50.4 volts and I’m wiring in a cell checker just to make sure they do not get unbalanced and if they do I have a connection in the back to brake the pack down into two 6s battery packs and I can put both of them on a balance charger image image image image image

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whats wrong with BMS? this reminded me of @hummie wanted to use 12 charger instead of a bms. :rofl:

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disclaimer Just so it’s clear to anyone reading, don’t do this unless you know exactly what you’re doing. Not using a BMS can cause a fire hazard.

But done correctly, it can work. I personally think it’s more hassle and worse in the end than just using a BMS though.

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Who needs fishpaper on batteries too?

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What cell checker are you using? You would need to run two of these to keep an eye on all the P groups voltage level. Monitoring total pack voltage is not going to protect you from out of balance issues.

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Also from experience of having a wired in cell checkers, you need a switch on them to turn them off when your not using the board, as they will drain just one cell in the pack. You can combat this by charging every single use but if you forget just once you will ruin one p-group. Alternatively you can just unplug them, but that is a pain in the but.

Ya i’m paranoid… I want every cell balanced… everytime… why I use lipos and smart chargers :stuck_out_tongue:

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Jus didn’t have any at the time of the build but it’s all clear brother it’s working like a dream

Yeah… Its a safety thing. I wouldn’t fuck around with that

I could ride my board without my helmet and say it’s all good because I never crash

Fishpaper is there because of safety. It can prevent shorts

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Thanks for the feed back buddy

If you want some more feedback on battery construction post pics of your battery build over here. Do you have pics of the ballance wire setup?

series-3-eod-iedd-suits-500x500

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There and you know for all the neg hate I’m not a damn professional Battery builder so oh well I didn’t use fish paper or what ever it’s working and I still don’t find a bms useful there cheap and crappy so I use a regular 50.4 volt charger and a battery cell checker and when they become unbalance I will use my ibcmax to balance them out thanks guys image image

Not hating… I gave you sound advice that can stop battery failures which can cause fires.

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Just to be clear. People aren’t bagging you for not using fishpaper, kapton tape and a BMS because it is unconventional not to. They are commenting because it is dangerous. Esk8 walks the line of legality in a lot of countries and the last thing people here want to see is governments cracking down on it because of boards catching on fire. Whilst I can’t force you to do anything, I highly recommend you get some fish paper and kapton and clean up the battery a bit. If not for the safety of yourself, family and others that you live with but for all of us in the community you are now a part of.

If you need any tips I’m sure there are plenty of people here that would be happy to help out :slight_smile:

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Good point well made. Take the advice please and don’t get bent when people are just trying to help.

Fish paper is not necessary. Cardboard, thick masking tape, anti vibration measures, or ample spacing all work. I think the whole point is to create distance between the serial packs, because the outer wrap can break down if rubbing together. The entire outer can is negative as you probably already knew. It is actually more important to add paper insulation rings to the positive ends of the cells. That’s where most shorts occur because the plastic melts under load and the nickle drops down to the top of the battery can.

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BMS= Battery Murdering System. Ballance lead wires can also lead to fires. In fact, the enclosure building guy on this forum had a story about that. It is technically more sound to use the battery checking method and split the pack in two to ballance on occasion, than to trust that a cheap electronic board from China isn’t going to allow drift and fail.

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I guess it comes down to do you trust yourself to do a better job than a computer. Considering I like to check, it’s hard to forget, and I haven’t gotten an electronic thing that hasn’t broken yet.

I’d rather watch or maybe just feel all the cells while charging at as high a current as Tesla would use! Feel like a star.

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Honestly, I opened up my 6A 50.4v charger and adjusted the potentiometer until it went to 49.8v. Since my batteries only ever charge to 4.15v per cell, my charge only BMS really isn’t doing anything at all and it shouldn’t be unsafe unless one of parallel groups is somehow defective and goes way over or under voltage.

As long as you you check your voltages every now and then and only charge to 4.1-4.15v per cell, BMSs are overrated.