You need inverters to run them, and you can't just put more battery on one inverter. The price is about 1:1 now for battery and inverter costs when I looked into it last.
You absolutely can put multiple batteries on one inverter. The limiting factor is the DC bus bar and breakers, not the inverter, which just needs to be sized to consumption.
Yes there's nothing stopping you, but economically a given kW battery installation stores about 4 hours of power.
There's 4 to 6 hours of peak renewable energy per day.
If you add more batteries, you increase power and energy at the same time and ratio: so for any practical home battery system you're cycling the cells daily, which means you your power for charging must match.
If you put more batteries on one inverter, then you're scaling a lot of other costs (BMS, bus bars and space) but you'll never actually be able to utilize that capacity - it'll sit idle most of the time because you can't get it in and out of the cells fast enough.
And if you run the numbers, the battery which can deliver 6.2kW is only about 1.5kwH in capacity. This matters because while discharging slowly is fine, to gain any economic benefit you need to be able to charge at essentially full power.
If you have 100kwh of batteries and only 6kw of AC connection then it would take 3 days of typical solar charging to get them to full capacity. And any kwh sitting there that you don't charge/discharge is costing you money for grid batteries - the economics still depend on being grid interactive.
The best demand signal in my local grid for example is exactly 1 hour wide. Which means s you get 4 15 minute intervals to basically try and dump power for the best price.
You need inverters to run them, and you can't just put more battery on one inverter. The price is about 1:1 now for battery and inverter costs when I looked into it last.
You absolutely can put multiple batteries on one inverter. The limiting factor is the DC bus bar and breakers, not the inverter, which just needs to be sized to consumption.
Yes there's nothing stopping you, but economically a given kW battery installation stores about 4 hours of power.
There's 4 to 6 hours of peak renewable energy per day.
If you add more batteries, you increase power and energy at the same time and ratio: so for any practical home battery system you're cycling the cells daily, which means you your power for charging must match.
If you put more batteries on one inverter, then you're scaling a lot of other costs (BMS, bus bars and space) but you'll never actually be able to utilize that capacity - it'll sit idle most of the time because you can't get it in and out of the cells fast enough.
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6.2kW 48V -> 230AC inverter is $300
And if you run the numbers, the battery which can deliver 6.2kW is only about 1.5kwH in capacity. This matters because while discharging slowly is fine, to gain any economic benefit you need to be able to charge at essentially full power.
If you have 100kwh of batteries and only 6kw of AC connection then it would take 3 days of typical solar charging to get them to full capacity. And any kwh sitting there that you don't charge/discharge is costing you money for grid batteries - the economics still depend on being grid interactive.
The best demand signal in my local grid for example is exactly 1 hour wide. Which means s you get 4 15 minute intervals to basically try and dump power for the best price.