Solar inverter/battery problem

QrizB

Not quite what you're asking for, but if your engineer friend is able to help you connect it and monitor it you can buy a 48v charger from eBay for about £20.

https://www.ebay.co.uk/itm/397246748472

This is a slow charger (2 amps) which would take a full day to charge each of your batteries, and is slightly lower than ideal voltage (meant for a different battery chemistry) so it won't get you to 100% charge, but it should be good enough to get your batteries back in business.

Reed_Richards

I recently had a similar problem, a communication failure between the inverter and the battery. It turned out that the communications cable had a very crudely made joint in the middle. I remade the connections using a proper junction box and that fixed my problem.

Magnitio

https://forums.moneysavingexpert.com/discussion/comment/81870611#Comment_81870611

It may be that the individual cells will need to be charged using an adjustable power supply until they are all at similar voltages . If the battery has a cell balancer, it may not function at very low voltages.

QrizB

Having to rebalance under these circumstances would be rather unusual, IMO. Mostly you'd top-balance a battery like this, and that would mean charging first.

Lockerbielad

Thank you all and sorry for the late response.

My new found forumite friend is looking into the cable theory. We tried using a new inverter/battery communication cable but it didn't resolve anything. He's exploring another idea he had about the cable.

In terms of a charger, Fogstar do a battery charger for £150 which I am prepared to buy if necessary. Considering the batteries cost almost £3000 it would be it if it resolves the problem.

I have to find someone/ a business or other who could charge them but I've not been successful so far.

We're even going to try the manufacturer to see if they can help, though the batteries are out of warranty by now.

Thank you all. Your ideas and suggestions are never lost and worth considering.

Lockerbielad

I was wondering that if the Dyness batteries are knackered and I need to buy some new ones, I'm not keen on buying some more Dyness ones since they haven't proved to be much good.

Could you please share your experiences of solar batteries: performance, reliability, price, brand name, etc

Thank you

QrizB

I was wondering that if the Dyness batteries are knackered and I need to buy some new ones

Wait until you've charged them, they might recover!

Do you know what the current voltage is? Above 40 volts (2.5 volts per cell) or below?

Could you please share your experiences of solar batteries: performance, reliability, price, brand name, etc

I've got a 16 kWh Fogstar battery. I built mine from a kit, but they also sell pre-assembled ones. Very cheap, I've had it a year, seems to work fine.

https://www.fogstar.co.uk/collections/solar-battery-storage

There's a big thread here about solar batteries (you might want to skip the earlier pages):

https://forums.moneysavingexpert.com/discussion/5568536/on-grid-domestic-battery-storage

Lockerbielad

Thanks QrizB.

The batteries are 42, 17 and 13 volts. Been advised of company that offers repairs and maintenance service. Their coming to have a look and see what needs to be done to the problem sorted.

I'm looking at alternative batteries just in case I end up needing new ones. Trying to understand this technology. Thanks again

Magnitio

https://forums.moneysavingexpert.com/discussion/comment/81874144#Comment_81874144

From the thread, I took it that the batteries were installed in an unheated environment in Scotland. The batteries should be protected from freezing weather or this issue will be repeated. Some batteries incorporate their own heaters to maintain a reasonable operating temperature. Where a heater is not included, people often insulate their batteries during cold weather, but it is important to remove this when warmer weather returns.

QrizB

The batteries are 42, 17 and 13 volts.

Ah, that's not great. LFP cells can be permanently damaged if discharged below 2.5 volts per cell (40v for a 48v battery like yours). The battery that's still at 42v might be saveable, but the other two are likely to be knackered.

The batteries should be protected from freezing weather or this issue will be repeated.

Yes, I'd agree with this.