Yes but only if you have Solar.
During the Cosy cheap period in the day the battery can be set to charge at max rate and if it gets there before the end of the cheap period your solar will power the house with any excess solar being sent to the grid (for payment if you have an export MPAN set-up).
But if you have no solar (at night for example) once the battery is charged you will import just enough to meet the house need. There will be no export as you can't import and export on the same pair of wires (to the grid).
One way to get around this apparent limitation is to charge the battery to max, export a bit, then charge it back up again still within the Cosy cheap period. If your battery can fully charge within the longer overnight cosy period you can add on the end a short export followed by a charge. If you're clever with the amount of charge and your battery carries you through the gaps you can charge in the cheap periods and export in the higher periods in-between. This will work particularly well in the summer when you don't have the load of the Heat Pump irrespective of whether you have solar or not. WW is great at managing this.
