The Seplos BMS V3.0 Balancing Issue. What is the problem here?

In today's video we are having a comprehensive look at the #Seplos #BMS V3.0 again and are trying to fix it.
The main problem is, that the balancer does not seem to work well, or maybe not even at all. All three battery packs were delivered with a massive imbalance of almost 0.3V at not even 55V.
I show you the three batteries and BMS and we measure the maximum possible charge voltage and the resulting deviation. INSANE!
I also try to use the 15A NEEEEEEYY to rectify the problem but was unable to even attach it to the battery due to construction design of the case and battery.
The solution was to manually balance one pack with the help of the light bulbs so we could charge it to the Seplos default voltage of 57.6V.
I left the BMS V3.0 balancer running over night at this voltage and was shocked by the results the next morning...

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[typxxilps]

There has been a BMS update for that BMS by Seplos as I had commented today. There is a video out from Seplos how to upgrade the V3 bms that is covering the balancing topic as they had said.
You might check it out now on the seplos youtube channel .

Good luck.

[tujuprojects]

I’m waiting when you stick that screw driver into wrong place 😊

[pragmaticcosmic]

Andy you need to change your exit slogan to ....stay safe ...stay charged and stay balanced!

[showme]

This Polo battery is not designed for us DIYers, its designed for the mass market, and so their customers would be ignorant of what's going on is side the pack. So in my mind your wasting your time trying to make a point that Seplos BMS mk3 in this product is anything special. The Mason on the other hand is design for us DIYers and so therefore balancing down to the single millivolt would count, it is their testing bed for the mass market products they want out there, as volume is king.

[chuksobi]

What's wrong with spending extra money to put a better balancer in their product, trust me china knows how to minimize a lot even if it ruins the whole product

[zeropointbalance]

Just an idea for BMS/battery manufacturers: Why not provide clear balancing instructions to their customers if they ever find the battery out of balance? Instructions that even a non-expert could follow? If an expert like Andy cannot balance this battery what chance would the average user have?

Example:
“If you ever find your LIFEPO4 battery out of balance, Please attach a 14V current limited supply/charger until the battery is balanced. **this may take up to 2 days**.”

Please note, the instructions must include an indication of how long since it may test the customer's

If they have to tell their customers “this may take up to 4 years” then they better include a better balancer or fix their balancer before releasing the product.

Then, reviewers could actually verify the instructions by inducing an imbalance, and then following the instructions. The battery only gets a pass if it can be balanced **per the instructions**.

[junkerzn]

Its going to oscillate a lot with the recovery voltage set at 3.6V instead of 3.4V. Not good. But also not necessarily a problem when multiple batteries are placed in parallel because the individual disconnects won't disconnect the whole set and leave the charge controllers with nothing to push against (which would cause the charge controllers to over-volt for a second each time the battery disconnects... if there were just one battery).

I do think the 3.4V over-voltage recovery default is too low but the parameters have to be really tight. Basically using a recovery default that low means that Seplos wants there to be a load or drain on the battery before it allows charging to resume.

The real question is whether the balancer can operate for a long enough period under those circumstances. It kinda sounds like the Seplos's balancing restrictions, possibly due to the design of the balancing hardware itself, is creating a problem, and the default settings probably aren't helping.

In anycase, I would care too... you don't want the normal operation of a battery pack to constantly be hitting a cell over-volt and disconnecting charging from the pack. That puts stress on multiple system components. In a single-pack system, for example, the disconnect will cause the charge controller to over-volt for a short period and possibly also cause the inverter to alarm.

[camielkotte]

I have noticed with JK BMS that the measurement of voltage as off by 0.2 volts compared by Victron and voltage meter. So I had to adjust/bias the BMS?! (I reassembled the whole battery. No difference. Still 0.2 volts off)
What if Seplos had a similar issue? Did you check if 3.45 V is actually correct?

[JayDee]

I've come to the conclusion Seplos leaves a lot to be desired.

[cooperhunter]

Where did you bought the cells?
Mine is bought in Seplos. I asked them about cells report. Henry gave 1000pcs cells report of their cells, where i found all 16s QR CODES of my cells. I was able to charge the battery from the first time to 55.8V, after which I had 2 cell protection. Up to this point, the difference was only 0.017v
GFB cells 280AH, the real capacity was between 298-299ah, bonus +1kwh😊

[airgead]

Perhaps you can get a contra connector for the balancing leads. Than make a snake cable on the contra connector for the You could also parallel a small permanently to the balancing leads. Ask Seplos for a contra (PCB) balancing / monitor leads connector.

[chuksobi]

Andy jkbms just lunched a new bms for storage systems with active balancer inbuilt....

[stanislavmlcuch]

Andy, Seplos offers seperate 2A Active balancer for BMS 3.0. Has Seplos sent it to you?

[quattrohead]

Seems like Seplos have !ucked up the default settings on their own batteries as well as the separate BMS like the 10E. How stupid can they be ?
Hopefully they will get this sorted with new recommended settings and/or firmware.

[wj]

Hello
Wher did you get the newest version off software for 3.0 v11 BMS?

[Dutch_off_grid_homesteading]

Heya, nice test but wen you started with the light bulb's I was thinking this is gone be a long way and so it was. 1, 5A balancer is that in total or is that for each channel ?

[LarryKapp]

Ah the ongoing saga of Seplos BMS balance . Maybe one day Andy can sleep without all the worry and bad dreams of 200mv deviations .

[AdventureMotoEnduro]

SINCE 2 jks bms clapped i thinking this one and active hitech

[patrickruiz]

hello the bms3.0 is ok buscan type A or type b please thank you !

[gwenaelg]

Coucou un grand merci pour votre travail et vos video,
Comment brancher 2 parck batterie de 280ah 48 v en lfp avoir une batteries des deux qui se décharge plus que l'autre un grand merci