The *ULTIMATE* BMS Guide

Everything you ever wanted to know about BMS's and more

-What is a BMS
-Different Types of BMS
-Bypass vs discharge
-What do those ports do?
-Safety
-worked installation example

TIME STAMPS

01:00 - WHAT IS A BMS?
01:55 - BYPASS V DISCHARGE BMS
04:00 - BMS DIFFERENCES
05:00 - WIRING GUIDE
06:15 - COMMON CHARGE AND DISCHARGE PORTS
08:50 - BALANCE HARNESS WIRING
14:40 - DEALING WITH CROSSING BALANCE WIRES
16:18 - COMPLETED BALANCE HARNESS
16:34 - A NOTE ON FLEX
16:50 - TESTING THE BALANCE HARNESS
19:20 - WIRING THE B- AND C-
26:32 - BLOOPERS!

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#BMS #howto #guide

[nickk]

As an American I heard “30” on those balance wires. Took me a good 2 minutes to realize you actually said “13”...😑. Great video man! Super helpful for my build.

[diydad]

Just a word of caution. Not sure if it was mentioned in the video but just beware of over-discharging your cells, so needless to say, keep an eye on your voltage. Bypassing the BMS will disable your low voltage cutoff protection.

[MILLERS]

Man am I thankful I just stumbled upon this video. I wired up my 40a BMS today and wired P- I’ll take that off. Makes total sense now.

[jonathanbayardo]

My guy I'm just starting a serious college project regarding battery packs and you literally just helped me to solve all my doubts about what to do coming up next with BMS connections. Thanks a lot Lee you're amazing!

[adeydawe]

Hey Lee, from someone who's very new to the Esk8 scene, I find your videos really educational as I really want to build my own mountain board. Hopefully once I've watch all of these vids I might be able to do so haha. Please continue to keep up these videos your doing a great job for the esk8 community. Well done 👍

[itsmedant]

Man I absolutely love the music in the background! Keep up the awesome videos Lee!

[greatdane]

Excellent explanation thanks mate.
I have been trying to understand the discharge side of BMS fo high current discharge applications for a long time and found endlessly conflicting info on the net. The info on bypassing BMS discharge control on high current draw applications was the missing piece of my puzzle.
Legend!

[jvall]

Great vid mate! Had an issue with my battery upgrade on my Evolve GT and decided to replace the ESC and BMS with new stuff. Was quite boggled when it came to picking a BMS. Went with a 40a smart BMS(looks similar to yours) but didn't realise I didn't have to use for discharge, only had the stock BMS to go off and didn't have a clue. So the original is actually wired for discharge then I guess.. The charge only seems so much more simple. 🤔 Thanks for all the info. It all makes alot more sense now.

[_nske]

Fantastic video mate -admirable attention to detail! I normally don't use Patreon but you're a top guy making top content, so I had to. I am not going to attempt wiring a BMS or making a battery pack myself, I just enjoyed understanding the logic/procedure/practices and filling some blanks. But what's most important is that you help educate/bring new DIY builders to the scene, keep up the great work!

[matzedias]

Your videos always come perfectly in time, so i don't have to annoy you asking how to xD

[FAB]

Thanks! Assembled my first battery with this guide, works perfectly!

[movation]

Great work lad perfect battery build but you extended the balance wires off camera this is a trick for new players may not be aware of. Only thing I would have done different would be add a inline fuse to charging port. But not required. 5 star build mate.

[explosivegardenreboot]

im new to this, have some good electrical knowledge but as i say im fairly new this one. just got my first bms, nickel strips and spacer system for a 36v ebike battery for use on my schwinn stingray chopper. gonna take my time on this build as i want to do it right. currently get about 12 miles from the bike based on a 36v brushless 500w hub. plenty of torque for acceleration up to 18mph. subed to ur channel and realy enjoy the videos. great knowledge

[simonchurchley]

Pretty handy video with a lot of gold nuggets of info there. Your batteries are a work of art. I will be after some improvements to my battery and BMS in the Icarus when the right VESCs come along.

[redreefbud]

Thanks 😁 I just ordered one of your smart BMS. Molicel p42, 12s. For my kaly deck and enclosure. It had trouble finding a Daly. Was watching this video and heard you say you had one 😁 thanks again and have a great day. Esk8 Freedom. Keep up the good work

[hansdampf]

Good advice with the smart BMS and the fish, kepton tape! Keep up the great work. Thx a lot

[MrRailcraft]

Quick tip. When you put some timecode into the description, you'll get an awesome feature. 😉

[wes]

Nicely done sir. I appreciate emphasis on clean safe work area. Lions are nothing to play with carelessly. One thing with these BMS builder/maker/diy videos ? Limited to zero mention of BMS WIRING SEQUENCE. I.E. 'connect negative & then sequentially wire individual cells', or 'wire negative lead, then positive lead and then connect cell bms lines, or it doesn't matter, wire it up with correct polarity & bms lines. Perhaps it's not relevant if no damage can occur from wiring from either pole & all cell lines in between. I have just not seen any mention of 'specific' BMS wiring sequence. Though I highly rate this video as quality information. Thanks for this video! Liked n sub'd

[modestasbitinas]

Thanks mate, I just got exactly what I need for the charging stuff.

[johnboy]

Just found your channel, really like your approach to building batteries and putting extra thought into making it as safe as possible. I'm more ebike as never been able to balance on a skateboard but have subscribed to help improve my own battery building. oh and keep the chilled background music