Faulty Dyness Batteries

Rackstar

Morning,

I had 6 DL5.0c batteries installed with my solar PV in November 2023.

I’ve had issues with the batteries from day one. The SOC would drop from ~50% to 20% and the batteries would be unusable. I contacted the installer immediately, they have been less than helpful, would not send someone back out to check the batteries. Instead they needed to deal with Dyness.

Eventually after some time and pressure they finally put me in touch with who I assume are Dyness via WhatsApp. We fully charged the batteries and exported the power from them 3 times, the third time the SOC didn’t drop and they told me all was good, batteries are fine. I pointed out that it SOC didn’t drop every time.

2 days later the problem returned. Went back through the same process with Dyness via WhatsApp. Only for issue to continue. This then went on for weeks, months, back and forth with no resolution.

One of the people that I’ve been dealing with from Dyness, is travelling from China to look at the batteries next week. (This in itself is a bit nuts)

I went down the supplied and installed route rather than sourcing my own batteries in order to avoid any issues, that has not worked out whatsoever. The installer would not come out and check the batteries, instead I was left dealing with Dyness via WhatsApp and then waiting months for this guy to come from China.

Has anyone else experienced similar? It appears the installer literally just install the batteries and doesn’t have the ability / knowledge to troubleshoot and or connect to the batteries and check logs.

To top it all off, the SOC dropped to ~20% last night and the batteries failed to charge at all during the night rate window.

SD_DRACULA

That's a bit nuts alright, I would have thought the installer can just bring them back to the supplier and swap them out then let them deal with the warranty.

I had 4 of the B51100 dyness for about 2 years myself and never anything major with them, they were rock solid.

One time the SOC would not go to 100% and dyness support sent me a firmware update which fixed the issue right away.

Maybe that's something you need to do as well but requires a bit of tech knowhow to make the cable etc.

I think that because you have 6 of them, they might not be wired optimally and the last one in the series is never charging fully, bringing the pack voltage down.

Dyness sent me this way of wiring them saying this is the best way and worked ok for me:

You will need three packs of the long cables to do this for your 6 packs.

Rackstar

https://www.boards.ie/discussion/comment/121864398#Comment_121864398

Thanks for the reply. My batteries are not wired as you showed.

If that’s the issue and I’ve waited months for this guy to come from China with this costing me money every time if happens, and the installer not bothering to come out and check, it’d really make you wonder.

SD_DRACULA

Now this config will work but if you see all the usual battery folk on youtube testing it they all find that it is a sub-optimal way of doing it (manual probably shows the same)

I see that you have the dyness dongle, you can get all your battery SOCs % from the app right?

Just check the SOC on each pack, I expect the last one to have the least % (they will never be 100% the same but if the difference is huge like 40% it will bring the voltage/SOC of the pack down)

If you find huge deviations in the SOC I would do this, connect one battery at a time and charge it to 100%, then once all are at 100% connect all 6 and in theory it should fix the SOC.

10-10-20

Having a rep come out to site can often be an indication of a bigger overall issue. You might find that they are visiting a number of sites while on the island.

If I was you, I'd demand that the installer provide a resource for the duration that the rep from China is onsite. Either that or they have their wholesaler provide a rep. No way is this supposed to be a 1:1 site inspection.

Plus I'm sure you know, but it's best if the system is running in the best state to potentially reproduce the problem - whether that means having a large heater available as a load or whatever. Also, do check that your environmentals such as temperature are good and be prepared to show it. 👍️

Keep us posted?

Rackstar

https://www.boards.ie/discussion/comment/121864673#Comment_121864673

Thank you, I have requested that the installer, their response was that if Dyness require us on site they will be on site. Not committing to anything as usual.

Rackstar

https://www.boards.ie/discussion/comment/121864673#Comment_121864673

Yes I have the dongle. It doesn’t give SOC per pack just an over all from what I can see.

Batteries appear to have come back to life.

graememk

This won't help with your case but With experience from other BMS's and building batteries:

SoC is generally a measured power in and power out, as voltage isn't an indicator when running, voltage is only an indication when full or empty.

Don't know the internal workings of the BMS in the dryness but generally it will reset itself to 100% either when total pack voltage hits a set voltage, or a single cell hits a set voltage.

The same sometimes happens on the bottom end. If a cell is hitting a low voltage alarm, some BMS reset itself down to a low state of charge.

It's likely there is a battery pack out of balance somewhere. (Possibly trying to fix them by cycling the batteries as suggested)

Is there a state of charge indicator on any of the batteries? Is there one that is out of sync or the rest of the pack, possibly as a workaround for now by removing one and letting the rest perform better.

SD_DRACULA

Well the app is not great if you can't see all the individual cells in a pack.

Not sure if you can connect the dongle to a PC but the windows software does show you all that, you might need an rs232 cable to do that though.

Rackstar

https://www.boards.ie/discussion/comment/121864747#Comment_121864747

Yes there is an indicator. Each battery has 5 green LEDs. This morning 4 had 2 LEDs lit and 2 packs had 1 lit. With Dyness coming next week I might just leave as is , thanks for suggestion though.

Rackstar

https://www.boards.ie/discussion/comment/121864770#Comment_121864770

No app is not great, but Dyness were able to access additional info with it installed.

10-10-20

https://www.boards.ie/discussion/comment/121864747#Comment_121864747

Yeah, really need to be debugging at an individual battery level rather than at an overall SOC level. I'm one who always clicks the "yes I know what I'm doing, give me access to the developer level diagnostics" whether I'm troubleshooting or not. 😂

SD_DRACULA

What inverter do you have? I have a funny suspicion that this might only be SOC drift and will only happen again the future after it's "fixed"

If it's a solis 5kw and in reality only charges at 3.6kw, divided by 6 batteries, the last pack would be lucky to get any juice

Also any battery, if it stays at a low SOC (without charge) will eventually kick in the auto-charge from grid to protect itself. So you'd need to fully cycle these often to keep an accurate SOC (it's a guesstimate anyway)

Rackstar

https://www.boards.ie/discussion/comment/121865302#Comment_121865302

..... yes Solis 5kw. Seems to charge at 100A / 5KW. I've 2 EVs and a heat pump so no issue cycling the batteries. Really hope it isn't a case of too many batteries for the inverter.

alfa_aficionado

All very good advice so far but surely the main issue here is that you had a contract with the installer and they need to come back and sort it out - not leave you as the end consumer to deal with the manufacturer. I'd be threatening to generate negative publicity / report them to trade body, SEAI etc.

alfa_aficionado

https://www.boards.ie/discussion/comment/121865302#Comment_121865302

Maybe they're better now - my Solis inverter can charge at a sustained 100A rate.

Rackstar

https://www.boards.ie/discussion/comment/121865715#Comment_121865715

Called installer this morning. Guy I was dealing with has left, the owner is supposed to be calling me back. The guy I had been dealing with was somewhat responsive and seemed to want to help but gave the impression his hands were tied, as in he couldn’t send anyone out.

Rackstar

Kept getting the line it was a warranty issue

SD_DRACULA

Sustained 5kw is good to charge the pack fully in about 6 hours but from the installer's point of view they wired them up as instructed by the manufacturer and that's that, it MUST be the batteries fault. In any case it's not really up to you to chase Dyness that's the installer's job, a lot of manufacturers won't even deal with the users.

Did dyness update the firmware on the batteries at least?

I assume the battery type is set to Dyness LV on the solis?

alfa_aficionado

https://www.boards.ie/discussion/comment/121865782#Comment_121865782

I think the fact that these were only installed in November 2023 and never worked properly indicates this is more likely due to the way they're installed / set up; even if it was a warranty issue (e.g. faulty cells within the battery) your contract is with the supplier and they have to fix it.

"If things go wrong, it is always the seller who should put things right. The seller must resolve any issue, so the product meets what was agreed in the contract. If the fault appears within the first 12 months, it is automatically assumed the fault was there when you bought it." - taken from the Consumer Rights Act 2022.

Rackstar

https://www.boards.ie/discussion/comment/121865878#Comment_121865878

Thanks, will try put pressure on again. The installer was from the north, will have to check out how the consumer rights work cross border.

alfa_aficionado

https://www.boards.ie/discussion/comment/121866051#Comment_121866051

Should be similar, although I think the timeframe for accepting it as an inherent fault is 6 months rather than 12.

enricoh

I think you are getting the runaround from the installer, I'm f@#ked if I'd be contacting the manufacturer in China.

If my garage installed a new battery, clutch etc in my car n it was a dud it's up to them to fix it n get compensated off manufacturer, I'd laugh if they suggested I sort it.

johndoe11

https://www.boards.ie/discussion/comment/121865722#Comment_121865722

Being meaning to check the Solis 6Kw inverter charging for a while, I never had an issue with dropping to 75a after 15 mins. I tested my solis last might at max charge. I got 92a for 1 hour then it dropped to 82a for the rest of it. Not sure what the trigger for the drop was. 12kw charging. Inverter got to max 65 deg c.

10-10-20

https://www.boards.ie/discussion/comment/121869338#Comment_121869338

Looks like a thermal throttle based on the heatsink temp. Does it have a fan? Is it in an attic?

I tried googling... it's not clear. Much of the documentation talks about the ambient temperature rather than the heatsink temperature.

https://www.boards.ie/discussion/2058180733/inverter-derating-with-temperature-solis

https://usservice.solisinverters.com/support/solutions/articles/73000558557-inverter-temperature-de-rating

Jonathan

https://www.boards.ie/discussion/comment/121869338#Comment_121869338

What exact model do you have? RHI-6K-48ES-5G or S5-EH1P6K-L? They both look very similar but the latter has improved battery charging circuitry.

johndoe11

https://www.boards.ie/discussion/comment/121869859#Comment_121869859

No fan, but out in the shed.

johndoe11

https://www.boards.ie/discussion/comment/121869896#Comment_121869896

The later, S5-EH1P6K-L.

Rackstar

https://www.boards.ie/discussion/comment/121866372#Comment_121866372

Spoke to the owner on Friday, seems like a decent guy and will endeavour to get sorted asap. Got a call from battery distributor then who went through some troubleshooting / fault finding. Distributor is coming with guy from China to find the issue and replace anything that needs replacing.

10-10-20

https://www.boards.ie/discussion/comment/121871166#Comment_121871166

Alright, that sounds a bit better. Please share the succulent technical details here. We love of a bit of troubleshooting.

graememk

https://www.boards.ie/discussion/comment/121872227#Comment_121872227

Fault finding, love it. It's the fun of the puzzle