Battery power help required

pochase

This looks more interesting than the Chinese solutions.

https://voltaconsolar.com/chargers/quasar-bidirectional-ev-charger.html#:~:text=£5%2C990.00%20Incl%20VAT.,vehicles%20into%20powerful%20energy%20sources.

With £6000 more expensive than the Chinese solutions, but you would need a charger anyway, so you can deduct that cost from the £6000. Plus it is 7.4KW for charging and discharging, double what the Chinese solutions allow for the discharge. Lastly it hopefully will be more up to spec and safety.

GrahamC55

The market is changing every day. Unfortunately there are many overpriced products with doubtful performance.
May I suggest you take a look at the YouTube channel "Fully Charged" which keeps pace with developments in UK quite well and may offer you some kind of solution or guide you in the right direction. There are already nice solutions for diverting solar or stored power to heat water or charge your EV. Battery options for those with Solar panels are still in their infancy unless you jump in at the deep end and go for a TESLA power wall or maybe LG systems setup. They are also quite far ahead with other options such as real "off grid"features such as power availability during a power cut.  Check out the channel its very educational.