On-grid domestic battery storage

QrizB

There's a thread over in "Consumer Rights" where someone's 8.5-year-old Pylontech batteries are supposedly failing and they're being compensated prorata under a warranty arrangement:

https://forums.moneysavingexpert.com/discussion/6646459/solar-battery-warranty

That's pretty elderly for a Pylontech system, I think? So fairly good news for battery durability?

I think this is the system the OP in that thread has, based around Pylontech cells and a Victron inverter:

http://graham.auld.me.uk/projects/moixa/

Also here: https://shkspr.mobi/blog/2023/08/review-moixa-4-8kwh-solar-battery/

An earlier Moixa "smart battery" system used two 25.6V batteries (8 LFP cells?) and a pair of Enphase micro-inverters:

https://www.ebay.co.uk/itm/134780473343 (this auction will eventually expire, but the photos are still up at present).

Also here: https://shkspr.mobi/blog/2016/03/meet-maslow-the-uks-answer-to-teslas-powerwall/

QrizB

If anyone has a Growatt SPH series hybrid inverter, there's a software configuration question over on the main Energy forum:

https://forums.moneysavingexpert.com/discussion/6647352/growatt-battery-discharging-too-early-octopus-flux-setup-help

QrizB

This thread seems as good a place as any to ask if anyone has had their power interrupted by Storm Goretti and, if so, whether their storage batteries (and any PV) have seen them through the outage.

Anyone want to share their experiences? Are there any things you'd do differently in future?

Netexporter

I did have some rueful thoughts about not pulling my finger out and getting my Fogstars installed, with a gateway. But not even a flicker of the lights in an area where we get cuts of varying lengths pretty frequently.

I'll have to make a new year resolution about not procrastinating, when I can be bothered to get a round tuit.

QrizB

Harwich is a long way from me, but if you're in the east of Engand and fancy a used 4.6kWh BESS then this listing might interest you:

https://www.ebay.co.uk/itm/227161674031

mickyduck55

Hi, my son is planning to "renew" his battery systen so will have three pylontec US3000 batteries which he will no longer need.  I have 3 US3000 batteries already which were purchased at the same time.  Can I add all three of his battreies to mine and does anyone know how / if my lux inverter will need reconfiguring?

Netexporter

You'll need to change the one new battery that is set to master to slave. Otherwise it shouldn't bother the inverter, as they are in parallel, so only adding capacity, not changing the voltage.

orrery

Netexporter said:

You'll need to change the one new battery that is set to master to slave. Otherwise it shouldn't bother the inverter, as they are in parallel, so only adding capacity, not changing the voltage.

Presumably, the newest battery and not the newest to mickyduck55

Heedtheadvice

Shouldn't be  problem

As said the newest battery ( if it is the latest released battery, a C suffix I think from memory and having the later/latest BMS firmware) should be the master. That is the one with the communication CAN connection to the Lux inverter that will control the other batteries.

You do not specify if all the batteries are the same or if some are the C type (US3000C). If there are any C types that must be selected as master otherwise as posted the newest.

Lots of info online some copied here for your help.

"

Key Setup Steps

"

• Master Identification: The battery connected to the inverter using the CAN cable (Type A for C-models) is the master.
• Inter-battery Communication: Use the RJ45 cables to connect Link Port 1 of the master to Link Port 0 of the first slave, and so on.
• DIP Switches: Keep all DIP switches in the default down position (0000) unless using an LV-Hub.
• Initialization: Turn on all battery switches, then press the red SW button on the master battery for 1 second to wake the system.
• Inverter Settings: Set the inverter to Pylontech/CAN bus protocol with a charge voltage of 52.5V–53.5V and discharge floor of 44.5V–53.5V. "
• For your additional batteries you can ignore that final check re battery voltage as it will already be set correctly.

You will need to ensure you have sufficient short comms link  cables to join from that master to the next battery and so on in series. This is as shown in the manual and how your current batteries are connected.

Similarly you will need sufficiently battery to battery power connections. That will be  a total each of red, black comms cables.

You will probably get sufficient from your son.

It would be best practice to make sure each battery has a similar amount of charge before connecting them. The BMS will sort out getting the same charge once they are all powered.

The Lux should then show you have doubled your capacity and work flawlessly.

mickyduck55

Heedtheadvice said:

Shouldn't be  problem

As said the newest battery ( if it is the latest released battery, a C suffix I think from memory and having the later/latest BMS firmware) should be the master. That is the one with the communication CAN connection to the Lux inverter that will control the other batteries.

You do not specify if all the batteries are the same or if some are the C type (US3000C). If there are any C types that must be selected as master otherwise as posted the newest.

Lots of info online some copied here for your help.

"

Key Setup Steps

"

• Master Identification: The battery connected to the inverter using the CAN cable (Type A for C-models) is the master.
• Inter-battery Communication: Use the RJ45 cables to connect Link Port 1 of the master to Link Port 0 of the first slave, and so on.
• DIP Switches: Keep all DIP switches in the default down position (0000) unless using an LV-Hub.
• Initialization: Turn on all battery switches, then press the red SW button on the master battery for 1 second to wake the system.
• Inverter Settings: Set the inverter to Pylontech/CAN bus protocol with a charge voltage of 52.5V–53.5V and discharge floor of 44.5V–53.5V. "
• For your additional batteries you can ignore that final check re battery voltage as it will already be set correctly.

You will need to ensure you have sufficient short comms link  cables to join from that master to the next battery and so on in series. This is as shown in the manual and how your current batteries are connected.

Similarly you will need sufficiently battery to battery power connections. That will be  a total each of red, black comms cables.

You will probably get sufficient from your son.

It would be best practice to make sure each battery has a similar amount of charge before connecting them. The BMS will sort out getting the same charge once they are all powered.

The Lux should then show you have doubled your capacity and work flawlessly.

Sorry for clarification all 6 batteries were bought at the same time with my sons install a day before mine.  They are all US3000 so no model "C".  I will get all cables from his install.
Re making sure they are all the same charge is this acheived by charging them one at a time?  I guess a simple way would be to get them fully charged at my sons before disconnecting and making sure mine are fully charged before I add his?