Future Honda HEV
I would use the Honda Motorcycle Exchange Battery.
Reasons why...
Cost... Cheaper battery Manufacturing and Auto assembly. To keep battery costs down I would allow the customer to buy direct from Honda( this will keep dealers from marking them up to much).
The biggest thing is there is no need for a Dealer tech to replace the battery!
Do it yourself
Resale Value....easier and cheaper to replace battery that leads to ICE model like Lifespan of Automobile.
I would switch to Sodium Ion battery as soon as possible because it's Safer and easier to recycle.
Home and Portable Battery Charging stations available. Charge at home and you have a PHEV.
EV only mode.
Anti- Theft.... serial numbers( visible and invisible).
You can also carry it into the house or work.
If it becomes a problem
I would love to see a City Type-R ( 5 door hatchback) using it's new platform.
The first vehicle using the Exchange Battery?
1.5 L DOHC V3 would give space on each side of the engine for up to 2 Exchange Batteries ( up against the rear firewall).
Cooling is going to be Key!!!
The batteries can also go in the boot but it would take away storage space.