BillyBob

@BillyBob to be honest solar as a rule, more so batteries can be quite the rabbit hole. What would happen if your battery packed up, would you have some money lying around to be able to immediately replace that size of battery? The other side of the coin is having multiple 5kw batteries such as FreedomWon or Pylontech and if one in the pack gives you issues you may be able to hobble along and reduce your loads whilst nursing the other remain batteries. Still again, there's the issues of ensuring that you have enough panels and your inverter has the capability to fully charge your batteries as well as ensuring that the individual cells in each battery pack get fully balanced regularly.
1. So to buy 1 x large battery bank or;
2. To buy several in a pack; is the question.
Liquidity, ability to monitor the batteries will inevitably help you in your decision making process. Am sure others here with more experience, will chime in with their knowledge and expertise and experiences.

In my house we are two adults, and we typically use 4 to 4.5 kWh from 17:00 to 7:00. So I think you need to work on that figure a bit. What things that you do during the night could you instead do during the day when the sun is up and you can grab some free power?

We have a 1C 10kWh battery. I can't actually use the 1C because my inverter is rated at 4.6kW. Anyways, I expect to have better than 50% of the battery available at 7:00, and that's after the water heating (heat pump, not an element) has run.

We run all the appliances and the pool pump during the day. At night it's TV, wi-fi, security, external lights (all LED), some interior lights, a bit of air fryer or kettle. Oh, and the fridges are all running.

The more load you can shift to the sunlit hours (using timers if need be) the better your battery's chance of making it through the night.

My situation - > 50% at 7:00 - means that I have a good chance of going a few hours if the worst possible scenario arises: A power outage early in the morning and PV not so good. Your battery is at it's lowest ebb when the sun is coming up.

Hi BillyBob, welcome to the forum!
No, it will not generate 7.168kWh, but it can theoretically store that much. However be aware that you cannot practically use the full theoretical capacity as the BMS will go into alarm mode at 10% SoC at the lowest. In addition there are internal losses that reduce the usable capacity. Also conceive your system such that you prevent to charge or discharge at more than 0.5C on order to preserve battery life. (C is the relative battery current with respect to its Ah capacity. I.E 0.5C on a 100Ah battery would be 50A.)