A current limiting device can be built or bought.
"Buy Separate controller for the batteries" will be just that
I am aware of one widely adopted field where current limiting devices are used (together with lithium battery): E-Bikes (and E-cars obviously)
10kwh is hardly "car material" and probably the investment will be too high.
Also playing with the higher voltages does have its own disadvantages.
For cost efficiency, probably the best choice.
1 kWh used to be around €/$ 0.20 2 years ago, depending where in Europe.
Now I hear people paying as high as 2 euro at peak..
I don't know if you can sell at the same price, say it's 50%, then that can be potential 300 a month with 10kwh battery.
You will have some conversion losses.
Batteries is normally the biggest investment, you already have them.
Keeping them at Operation temperature doesn't have to be a big problem.
10 cm of polyurethane foam and a few temperature controlled heating pads will Protect the cells when needed.
Those aren't the costs, or worth the hassle / danger of the 10kwh lithium bomb Inside your home
The Revo isn't cheap for its own power consumption.
Besides this, it's loud.
It can charge (from my head) 40A maximal via grid, 90A (theoretical) via solar or combined.
The 5500 solar is in reality 4400.
Consequently, the 40A probably will be close to 30A.
Keep in mind the loss of +3A for grid connection.
The +2A for being turned on..
30A is realistic the max you can charge
10kwh at 44v, 230Ah.
7.5 hours charging time.
Then the feed back to the grid.
In the first firmware version I got, there was a nice setting to do just this (!!!)
While living off grid, I thought it was a neat feature.
Sadly with the first update it wasn't available anymore.
As I don't have CT sensor attached, nor grid, it can be "hidden" for me now.
It makes sense that you should be able to tell the start time to dump the stored energy to the grid, not only excess power after the batteries are charged.
You need to contact
ella@soroups.com for better explanation if this feature is still available, or not.
Still...
Roughly 8 hours to charge the battery.
4 hours to discharge.
With a switch it should be possible to turn the unit off when it isn't charging or discharge , to preserve the 250 watt own consumption.
If it's on 24/7 you are looking at 10kw power consumption just for being powered on.
I can not confirm this with my setup.
No grid,no constant drain of 160 watt due to this.
The 5500 watt unit does consume about 75-100 watt for just being turned on.
Just like the mppt eats the first 100 watt from solar, that is never seen again, for the whole daytime of charging.
If the panels produce high enough voltage, but not yet enough amperage, it will eat from the battery.
During a long lasting rain it might be better to turn off the connection to the solar panels to preserve energy.
Living in Thailand, not a problem for me.
When I lived in Holland and a shower might me measured in days or weeks...
Especially during winter, the light is never enough to produce the 100 watt, and compensate for the many hours it was too low. There might be a small opening, less rain and gray.. not enough.
If I would be using the solar system there, I probably would make a light sensor and contactors setup to only connect with enough light.
I like your idea, even if it's not just for making money, re-use what you have available is good.
I have a different idea for you.
Perhaps you like it.
It's a bit the same as I do.
I have 43x panels (27x325 / 16x345w) way overkill on the many sunny days, but enough to last a week of rain with the 50kwh battery.
Little bit of wind turbines, that I need to change, as there isn't enough wind usually to even start them.
I have GPU's that do crypto mining to consume my excess energy, and are simply reduced or turned off when there isn't energy available.
Nvidia 3070 second hand will cost about 350 euro. And makes about 1.50 a day.
3.5kw energy per day.
3 cards, they will heat up the battery if you like
Even @ - 30c not a problem
Power supply, main board..
Lots of miners stopping (due to high energy price) should be fairly available.
Complete "mining rig" with power consumption of 10kwh per day (400-450w) should pay about €4-4.50 a day, with current low rates.
(The change to ETH 2.0 and different income streams are incorporated in this calculation)
Feeding back to the grid is something I have no experience with.
If you already have a setup that is capable of doing so, and your country pays a good amount of money for it, without too many restrictions..
Go for it.
In Thailand only a handful of brands and models paid enough Brown paper bags to be allowed, and even being allowed doesn't mean you can.
The grid is unstable, homes have normally max 10A power.
While it's cheap, 4-5 thb (€0.11-0.14) feeding to the grid (if you get permission) only gives 1 thb (€0.03) per kWh.
I don't know how long the power is cheap, how many hours you can buy at a low price, nor how many hours you can sell at a high price.
One Revo II 3.2 or 5.5 model can realistic charge 30A (on paper 40A) of 44v (or higher voltage, depending on your setup)
I don't know if it can discharge at maximal capacity to the grid.
In my memory of the first firmware I saw 2 years ago, it was the same as charging from the grid, 40A.
Even if it can do 40A, 1750w, about 6 hours for charge and 6 for discharge.
2 parallel units of 3.2kw would reduce the time, not sure if it will double the 160 watt for grid connection.
Again, Ella should be able to tell this
What does work is to use the additional stored energy for crypto mining