In Alaska have issues with lithium batteries not charging correctly

[Wildman13]

Hey everyone,

My wife and I live on thew road and currently in Alaska for the summer in our small Travel trailer. I built the system myself from knowledge in this group and it's worked fine for almost 2 years.

I have a Growatt All in One 24v system with TWO 206ah SoK Batteries.

A few weeks ago I hit the tongue jack button and it seemed like a tripped a breaker, no power all of a sudden. After getting out the volt meter I determined that my 24v to 12v buck step down converter had gone bad. After using 1 battery to the system and waiting a week for a part I was back in business (at least I thought so).

I charged the battery I had been using back up some but both batteries weren't at the same voltage. I have a battery balancer on them so I figured I would see how much they "balanced" during my 3-4 hour drive that first day and if need be charge up the low battery some more once getting to a new spot. I have a Victron battery charger and a Genny,.

When I got to camp that Night and went in the rig I could smell an electrical burn (never good). My battery balancer had burned out and the battery I had NOT been using and had the fuller charge was at 17.1 Volts!!! I unhooked the batteries and hooked just that 17 volt one back up and went out and used the tongue jack several times to get it down and voltage.

That was like June 28th. Over the last week that battery has been very wonkey and I've been monitoring it multiple times a day. When they system is hooked up and charging from solar or the truck while driving (all going through the all in one) that battery is charging at like 15.1 to 16 volts while the other has a regular voltage of like 13.35. As soon as I put a load on the batteries & run something (other than LED lights) the "wonky" battery voltage drops down to a reading of like 12.87, the other battery is still around the 13.35 and seems to be acting normal.

I am using a volt meter directly on the batteries whole hooked together.

I unhooked them all a few days ago and measured them after getting a reading like the 12.87 and 13.35 and then the 12.87 measured back at a normal range of 13.4 or something and the other was right where it was when hooked up.

The last 2 days while driving and charging the all in one has hit a fault both days because I have the stop charging safety set to 30 volts. Both days the "wonky" battery has hit like 16. something Volts while the other is at its normal 13.35- 13.4 ish range.

Last night I unhooked everything again and charged the lower battery to full with the victron charger 13.52 volts (close to full) and then put the charger on the other battery and it wouldn't do anything as it read 14.67. This morning after using the coffee pot, toaster, starlink etc. I got more readings. The "Wonky" battery was charging at 15.15 again and the other other at 13.4.

I have ben trying to contact "Current Connected" (where I got the batteries) since Friday the 29th. They of course took off until yesterday (which I totally Understand) but they have been to busy to take my calls or reply to my emails other than two 1 sentence replies that don't make sense and confirm they actually didn't read what I sent them.

I am guessing I have a bad BMS, Bad cell(s) or both.

Being In Alaska means it's almost impossible to find people / parts to fix things so I'm hoping to get some feedback here.

Sorry for the long post and thanks in advance.
Lee

 

[sunshine_eggo]

Are you saying you pulled 12V off one of the 12V forming your 24V bank? If that's the case, that's a HUGE no-no. NEVER do this. Ever. Even in an emergency. Come up with a different solution, e.g., jumper cables to the truck battery and run the truck engine when you need to charge the 12V. If you still have the old on-board AC-DC converter, plug it in and let it provide 12V power.

The battery regularly reading elevated voltage likely has a failed BMS and damaged cells. I suspect it's done.

Only hope for a limp along:
Dismantle 24V bank.
Wire 2X 12V in parallel.
Charge to 14.4V and hold for 2 hours.
Rewire in series and pray.

 

[Wildman13]

Are you saying you pulled 12V off one of the 12V forming your 24V bank? If that's the case, that's a HUGE no-no. NEVER do this. Ever. Even in an emergency. Come up with a different solution, e.g., jumper cables to the truck battery and run the truck engine when you need to charge the 12V. If you still have the old on-board AC-DC converter, plug it in and let it provide 12V power.

The battery regularly reading elevated voltage likely has a failed BMS and damaged cells. I suspect it's done.

Only hope for a limp along:
Dismantle 24V bank.
Wire 2X 12V in parallel.
Charge to 14.4V and hold for 2 hours.
Rewire in series and pray.

I'm saying I unhooked the batteries from the system and each other and had 2 separate 12v batteries. I then used one of the 12V batteries and bypassed the all in one and just hooked it up to the 12v camper system like you would normally do.

 

[Wildman13]

Are you saying you pulled 12V off one of the 12V forming your 24V bank? If that's the case, that's a HUGE no-no. NEVER do this. Ever. Even in an emergency. Come up with a different solution, e.g., jumper cables to the truck battery and run the truck engine when you need to charge the 12V. If you still have the old on-board AC-DC converter, plug it in and let it provide 12V power.

The battery regularly reading elevated voltage likely has a failed BMS and damaged cells. I suspect it's done.

Only hope for a limp along:
Dismantle 24V bank.
Wire 2X 12V in parallel.
Charge to 14.4V and hold for 2 hours.
Rewire in series and pray.

Also Can you explain why you can't pull the system apart and use 1 battery, if that's what you are saying, and then put it back into the system? I mean I can take 1 AA (out of 3) out of my headlamp put it into something else and then put it back no issue. Its not exactly the same for an example but it's close. I mean $1,000 lithium battery with BMS should be able to do things like that. It might very well not like you are saying but that doesn't make sense to me which is why I'm asking for an explanation so I can better understand.

Thanks

 

[mikefitz]

At some point the BMS in the battery showing the high volts failed to work correctly, perhaps being damaged when the 24 to 12 converter failed.
Although the 206 Sok has high capacity, the BMS has a relatively low charge and discharge current, suggesting a 'cost limited' BMS.
Since its easy to access the cells in the Sok, the bad battery can be investigated.
It's understandable that the actions taken by the OP seemed reasonable at the time, the batteries have a BMS to protect in the worst case and a ballancer was installed correct the mid point. My guess is that the battery was already damaged.
This is yet a further example of possible 'bad happenings' that result in having 12v lithium batteries, each within own 4s BMS, in a series string .

 

[sunshine_eggo]

I'm saying I unhooked the batteries from the system and each other and had 2 separate 12v batteries. I then used one of the 12V batteries and bypassed the all in one and just hooked it up to the 12v camper system like you would normally do.

Ah. Big difference. Paralleling the two 12V would have been the better option - 2X the capacity and both batteries would have been nearly at the same SoC.

Also Can you explain why you can't pull the system apart and use 1 battery, if that's what you are saying, and then put it back into the system?

Didn't say that. It wasn't clear to me that you broke the battery down; however, by using only one of them and not both in parallel, AND because you didn't charge both to full in parallel before putting them in series, you have a 24V battery with the 12V batteries out of balance. They must both be at 100% when the 24V system is at peak voltage.

I mean I can take 1 AA (out of 3) out of my headlamp put it into something else and then put it back no issue.

That's not true if in series. The useful capacity of the 3 cells will be limited by the weakest cell. When the light stops working, you will find that the transplanted battery will be depleted with voltage lower than the other two, and the other two will have

Its not exactly the same for an example but it's close. I mean $1,000 lithium battery with BMS should be able to do things like that. It might very well not like you are saying but that doesn't make sense to me which is why I'm asking for an explanation so I can better understand.

Doesn't matter if you spent $10,000 on a battery. You can't put a battery with one state of charge in series with another battery at a different state of charge and expect trouble free operation.

I charged the battery I had been using back up some but both batteries weren't at the same voltage.

This should have read:

"I charged both batteries to full individually and then again in parallel before wiring in series.

(NOTE: In retrospect, I realize this was sufficient info for me to understand you were using only one battery.)

I have a battery balancer on them so I figured I would see how much they "balanced" during my 3-4 hour drive that first day and if need be charge up the low battery some more once getting to a new spot. I have a Victron battery charger and a Genny,.

Victron battery balancers are anemic. They are sufficient to maintain a good balance, but they can't take a horrific imbalance and make it right unless allowed to do so over a long period of time with deliberate efforts on the part of the user.

 

[Supervstech]

Also Can you explain why you can't pull the system apart and use 1 battery, if that's what you are saying, and then put it back into the system? I mean I can take 1 AA (out of 3) out of my headlamp put it into something else and then put it back no issue. Its not exactly the same for an example but it's close. I mean $1,000 lithium battery with BMS should be able to do things like that. It might very well not like you are saying but that doesn't make sense to me which is why I'm asking for an explanation so I can better understand.

Thanks

When you take one AA battery out, use it, then put it back in series, you aren’t then CHARGING the series of batteries, you are only discharging, then throwing them away…
With a house bank that is then charged, the low cell will take FAR more current to charge, and the full cell will keep charging until the charger series voltage is reached.

Now, the battery is supposed to disconnect when it’s internal cells reach high limit, but things fail. Especially when they are subjected to a device failure.
But the RULE is, with series connected batteries, they must ALWAYS AT ALL TIMES be charged and discharged equally. or they get out of balance, and your results occur.
Any time a battery used in series is ever used out of series, the entire bank needs to be paralleled and charged fully up to the cells full charge.

 

[Zwy]

Hey everyone,

My wife and I live on thew road and currently in Alaska for the summer in our small Travel trailer. I built the system myself from knowledge in this group and it's worked fine for almost 2 years.

I have a Growatt All in One 24v system with TWO 206ah SoK Batteries.

A few weeks ago I hit the tongue jack button and it seemed like a tripped a breaker, no power all of a sudden. After getting out the volt meter I determined that my 24v to 12v buck step down converter had gone bad. After using 1 battery to the system and waiting a week for a part I was back in business (at least I thought so).

It appears you are using a pair of 12V batteries in series to make 24V. Keeping these in balance can be tricky, best practice is a multi bank charger that will charge each battery individually.

I charged the battery I had been using back up some but both batteries weren't at the same voltage. I have a battery balancer on them

What balancer and type?

so I figured I would see how much they "balanced" during my 3-4 hour drive that first day and if need be charge up the low battery some more once getting to a new spot. I have a Victron battery charger and a Genny,.

You should have put both batteries in parallel and charged the batteries using the Victron and generator until both batteries were fully charged.

When I got to camp that Night and went in the rig I could smell an electrical burn (never good). My battery balancer had burned out and the battery I had NOT been using and had the fuller charge was at 17.1 Volts!!! I unhooked the batteries and hooked just that 17 volt one back up and went out and used the tongue jack several times to get it down and voltage.

Toast. Put a fork in it, it's well done.

That was like June 28th. Over the last week that battery has been very wonkey and I've been monitoring it multiple times a day. When they system is hooked up and charging from solar or the truck while driving (all going through the all in one) that battery is charging at like 15.1 to 16 volts while the other has a regular voltage of like 13.35. As soon as I put a load on the batteries & run something (other than LED lights) the "wonky" battery voltage drops down to a reading of like 12.87, the other battery is still around the 13.35 and seems to be acting normal.

I am using a volt meter directly on the batteries whole hooked together.

I unhooked them all a few days ago and measured them after getting a reading like the 12.87 and 13.35 and then the 12.87 measured back at a normal range of 13.4 or something and the other was right where it was when hooked up.

The last 2 days while driving and charging the all in one has hit a fault both days because I have the stop charging safety set to 30 volts. Both days the "wonky" battery has hit like 16. something Volts while the other is at its normal 13.35- 13.4 ish range.

Last night I unhooked everything again and charged the lower battery to full with the victron charger 13.52 volts (close to full) and then put the charger on the other battery and it wouldn't do anything as it read 14.67. This morning after using the coffee pot, toaster, starlink etc. I got more readings. The "Wonky" battery was charging at 15.15 again and the other other at 13.4.

I have ben trying to contact "Current Connected" (where I got the batteries) since Friday the 29th. They of course took off until yesterday (which I totally Understand) but they have been to busy to take my calls or reply to my emails other than two 1 sentence replies that don't make sense and confirm they actually didn't read what I sent them.

I am guessing I have a bad BMS, Bad cell(s) or both.

Being In Alaska means it's almost impossible to find people / parts to fix things so I'm hoping to get some feedback here.

Sorry for the long post and thanks in advance.
Lee

 

[Wildman13]

It appears you are using a pair of 12V batteries in series to make 24V. Keeping these in balance can be tricky, best practice is a multi bank charger that will charge each battery individually.

I have the one victron 17 amp charger, this is what I used in the very beginning per instructions of "Charge each battery separately to 100% and then hook together"

What balancer and type?

It was one Watts 24/7 sold me when I got the all in one and panels. $30, nothing fancy.

You should have put both batteries in parallel and charged the batteries using the Victron and generator until both batteries were fully charged.

I was unaware of that and had just got done also having a suspension issue fixed on the trailer. I had multiple issues at the same time, both serious. I assumed I could just charge them individually like to did in original set up after moving that day.

 

[Wildman13]

When you take one AA battery out, use it, then put it back in series, you aren’t then CHARGING the series of batteries, you are only discharging, then throwing them away…
With a house bank that is then charged, the low cell will take FAR more current to charge, and the full cell will keep charging until the charger series voltage is reached.

Now, the battery is supposed to disconnect when it’s internal cells reach high limit, but things fail. Especially when they are subjected to a device failure.
But the RULE is, with series connected batteries, they must ALWAYS AT ALL TIMES be charged and discharged equally. or they get out of balance, and your results occur.
Any time a battery used in series is ever used out of series, the entire bank needs to be paralleled and charged fully up to the cells full charge.

I was told to charge them separately and then put them back together, which i did but after the one went to 17 volts. no fix

 

[Wildman13]

Ah. Big difference. Paralleling the two 12V would have been the better option - 2X the capacity and both batteries would have been nearly at the same SoC.

I did charge them both to approximately the same voltage the day after the 17.1 volts. 13.37 and 13.35. Then put them back together and all the same issues of the one being wonky. I was originally told to charge each battery to full on set up and then put them together. I also charged them both up again with the charger to full and still isuues.

I also had a major suspension issue when the 24v to 12v balancer went out so my attention was focused on getting both issues fixed and back on the road.

My battery charger is the 17amp victron, the battery balancer was just something that I got from Watts 24/7 when I picked up my panels and all in one. Can you recommend a decent battery balancer? I have to order a new one on amazon as it is.

Also, should I even bother trying to wire in parallel at this point?

 

[Wildman13]

UPDATE: I opened the batteries per Current Connected and got some new voltages. Measured a bunch of things to do some comparisons.


Batteries

Measured at B- and positive inside battery (skipping BMS)
- Good: 13.37
- Wonky: 13.37

Measured after put back together:
- Good:: 13.37
- Wonky: 13.37

Measured breaker turned back on (minimal 12V pull)
- Good: 13.35
- Wonky: 13.07

Measured inverter & starlkink on ( -5.68 amps 146 watts draw)
- Good: 13.31
- Wonky: 12.69

Measured after turning solar back on to charge (+12 amps 350 watts)
- Good: 13.50
- Wonky: 15.67

I'm not an expert but to me this says the cells are most likely OK and the BMS is messed up on the "Wonky" battery.

Inputs, Thoughts? Additional comments?

I did not pull the cells apart for individual readings because I did not have authorization for that and when I got the 13.37 reading it seemed fine. Maybe I'm wrong here though.

 

[Tomthumb62]

UPDATE: I opened the batteries per Current Connected and got some new voltages. Measured a bunch of things to do some comparisons.


Batteries

Measured at B- and positive inside battery (skipping BMS)
- Good: 13.37
- Wonky: 13.37

Measured after put back together:
- Good:: 13.37
- Wonky: 13.37

Measured breaker turned back on (minimal 12V pull)
- Good: 13.35
- Wonky: 13.07

Measured inverter & starlkink on ( -5.68 amps 146 watts draw)
- Good: 13.31
- Wonky: 12.69

Measured after turning solar back on to charge (+12 amps 350 watts)
- Good: 13.50
- Wonky: 15.67

I'm not an expert but to me this says the cells are most likely OK and the BMS is messed up on the "Wonky" battery.

Inputs, Thoughts? Additional comments?

I did not pull the cells apart for individual readings because I did not have authorization for that and when I got the 13.37 reading it seemed fine. Maybe I'm wrong here though.

I'm no expert either but yeah it does look like the BMS is damaged. What did Current Connected say to do? I would default to whatever they say (since this probably under warranty) versus anything anyone on this forum (other than @HighTechLab aka Dexter at CC might say).

 

[Wildman13]

I'm no expert either but yeah it does look like the BMS is damaged. What did Current Connected say to do? I would default to whatever they say (since this probably under warranty) versus anything anyone on this forum (other than @HighTechLab aka Dexter at CC might say).

I just got this info and sent it to them, per their request yesterday. It would be great if they got my email and responded this weekend since I've been trying to get a response from them since the 30th but it's the weekend again and I don't think they work on the weekend.

At least I'll be near Palmer / Anchorage next week where I can actually get a part shipped to.

 

[HighTechLab]

My tech Jason is working on this...I'm not totally up to speed here but know that Jason will make sure @Wildman13 is taken care of.