DIY Batteries Discount Code

[johnb2713]

If anyone is going to have a go at battery building, Fogstar have a discount code at the minute 'DECEMBER16' which gets you 15% off this UK based companies already competitive prices.

 

[Bob Smith]

Your message must have been popular. They removed it

 

[Bob Smith]

https://www.fogstar.co.uk/collections/lifepo4/products/eve-lifepo4-280ah-prismatic-cell
I must admit when I see this, I am very tempted to build my own battery. "no more" constraints from suppliers.

And as you have several times said, regardless of the brand (Solax, Polyntech, Growatt, Solaredge etc...) and are all made from the same cell unit...

 

[johnb2713]

I think it was a one day only code.

The batteries along with a Seplos BMS which emulates the protocols of several other manufacturers, it allows communication with the inverters. My battery is twice the capacity of a growatt battery, it has a 5kW inverter and still costs less than the growatt battery half its capacity
.

 

[tcarmich]

I think it was a one day only code.

The batteries along with a Seplos BMS which emulates the protocols of several other manufacturers, it allows communication with the inverters. My battery is twice the capacity of a growatt battery, it has a 5kW inverter and still costs less than the growatt battery half its capacity
.

John does this mean it could be mixed as an extra battery on a Growatt sph6000? ie 1x growatt battery with 1 x DIY, and if so how does this align with Growatt support dialing in to the SPH...
thanks

 

[johnb2713]

John does this mean it could be mixed as an extra battery on a Growatt sph6000? ie 1x growatt battery with 1 x DIY, and if so how does this align with Growatt support dialing in to the SPH...
thanks

It's not something I've tried, however, Growatt and many other manufacturers seem to accept Pylontech protocol (the communication talk between inverter and BMS). My Seplos BMS says it's emulating Pylontech and this is confirmed by the inverter it's talking to, the Victron thinks it has a Pylontech battery attached.

Here is a screenshot from the Seplos BMS.

The Growatt inverter and battery seem to be configured in the same way i.e. a Master battery address and then secondary battery address etc (just setting a switch). The comms are done by Canbus which makes connecting easy. I think I'd be fairly confident it would work, it's no big deal anyway, if it wouldn't talk you could still connect up the DC, allow the BMS to look after the batteries and the thing would run in the same way.

The Growatt inverter manual confirms it will talk to Pylontech batteries.



I used an additional inverter to make my battery AC coupled, a) to get more inverter power available (the SPH6000 only provides 3kW from batteries. b) To get more charging power (21 kWh in 4 hours). It would certainly save on cost and complexity using the existing inverter a 14 kWh battery with BMS should come in at under £2500.

 

[tcarmich]

It's not something I've tried, however, Growatt and many other manufacturers seem to accept Pylontech protocol (the communication talk between inverter and BMS). My Seplos BMS says it's emulating Pylontech and this is confirmed by the inverter it's talking to, the Victron thinks it has a Pylontech battery attached.

Here is a screenshot from the Seplos BMS.
View attachment 14716
The Growatt inverter and battery seem to be configured in the same way i.e. a Master battery address and then secondary battery address etc (just setting a switch). The comms are done by Canbus which makes connecting easy. I think I'd be fairly confident it would work, it's no big deal anyway, if it wouldn't talk you could still connect up the DC, allow the BMS to look after the batteries and the thing would run in the same way.

The Growatt inverter manual confirms it will talk to Pylontech batteries.

View attachment 14715

I used an additional inverter to make my battery AC coupled, a) to get more inverter power available (the SPH6000 only provides 3kW from batteries. b) To get more charging power (21 kWh in 4 hours). It would certainly save on cost and complexity using the existing inverter a 14 kWh battery with BMS should come in at under £2500.

Thanks John, thats a lot of food for thought. Do you know if the 3kw limit is likely a software restriction that may be lifted or a hard limit? (and is the 3kw limit per battery per SPH6000 or for both batteries, which is even more limiting?)

Could this approach allow the SPH6000 to support more than two batteries which seems a big limitation right now

thanks tim

 

[johnb2713]

Thanks John, thats a lot of food for thought. Do you know if the 3kw limit is likely a software restriction that may be lifted or a hard limit? (and is the 3kw limit per battery per SPH6000 or for both batteries, which is even more limiting?)

Thats the limit on the inverter which was a huge disappointment for me, I should have RTFM (Read The Manual). My Victron is 5kW continuous and 9kW peak, a bit of difference for a lower rated inverter (5kW).

Could this approach allow the SPH6000 to support more than two batteries which seems a big limitation right now

thanks tim

Thge inverter doesnt really do anything by way of support to my knowledge. It uses the % SOC and probably some voltage, current and kWh data. This is only displayed, I'm sure it will read the voltages itself on the input to determine high voltage alarm etc.