What do you mean by "peak" hours? What tariff are you on?. What Steve has described work fine for charging over night, but as soon as your charge period is finished, if there is no sun you will begin to pull from the battery. So if you are on Economy 7 and set your full charge period of 7.5 hours the grid will fill your battery, and then your base load will be covered by the grid until the end of your charge period, say 7.00am, and then you will pull from the battery until the sun gets going. So if that is what you mean by peak usage, then the above will work. If you are on Flux for example, and want to charge from 2-5 am do the above settings. But if you want to save your battery to discharge at Flux peak times (4-7pm) then you will have a lot of manual fiddling to do unless you want to go down the Home Assistant or automation route. You will basically have to set your battery discharge rate to 0%. This will stop any discharge during the day, and will mean you import from the grid at the Flux day time rate. Then at 4.00pm you will need to set your battery discharge rate back to 100%, and engage discharge or export and switch ECO off for the duration of the discharge, and then remember to engage it again afterwards (I think there is some variability between generations of inverters - I'm not sure but I think Gen 3 hybrids may reset ECO automatically, but don't hold me to that).A lot of faf,!!!!