If it is becoming an extension of the battery, and not just a booster like for a cell phone, then cooling it needs to be considered. Except for a glaring exception, traction packs have at least a fan to move air over them.
Sure, I'm totally good with that thought... That could easily be built into my theoretically Li-ion battery pack ! BTW: Roughly speaking ~100 lbs of my go to 26650* 5100 mAh /18.9wh Li-ion battery would be about ~455 total batteries. But let's lessen the number down to ~425 batteries because of the case, wiring, connectors, & your needed cooling fan: we will still yield about ~8Kwh's. Rob43 * My favorite Li-ion size
So.....what's the problem with that ? Do you notice any significant difference in acceleration, handling or gas mileage with an adult passenger in the car ? No ?? Well 100 pounds of battery would be roughly half the "average" adult passenger these days.
In theory it's possible, but you need to find a long stretch of road that is clear of all obstacle, because otherwise the tanker can't fly low enough long enough for you to get a full charge.
I have a retired engineer buddy who was thinking of adding batteries in the back saying he was going to connect out the window to the J1772 with a plug... before learning more here, I said there is probably a way from inside the car. Of course we opened the hatch and there was an access panel to the backside of the J1772... needless to say, you can't charge and drive at the same time. Software is involved there unless you find the sweet spot where the regen cycle inputs voltage? The again there would be software quirks wondering, "wtah is going on here?"
How unreasonable would it be, whilst on a long trip, to charge while driving, run out the battery, charge again and keep doing this? Sounds like insanity but would probably reduce battery life.
The only way to do that would be with Charge Mode, so I'll guess that that's what you mean by "charge while driving." That's easily done, but will usually result in more fuel use per mile than just driving normally due to the energy lost in converting gas to electricity. And yes, that would reduce the life of the battery since they have a limited number of full cycles before the need replacing. It's a big number, but not big enough to disregard.
If you are talking about Charge mode (using the gasoline engine to charge the battery), there are only a few scenarios where this makes sense. In general, it is counterproductive to use the gasoline engine to charge the battery, and then use the battery to move the car, due to conversion losses at each step; it is more efficient to just use the gasoline engine to directly move the car. As I recall, one scenario where Charge mode works is when one is coming off of a long highway stretch, and one wants to use the battery for in-town driving. But even then, it is tricky. With the battery drained, the Prime is incredibly efficient operating as an ordinary Prius hybrid.
OK - Lets Say 4000 Charging Cycles by 100,000 miles ( 25 Miles per charge ) for 100% EV Mode Engine Running in charge mode while driving lets say 30 Miles of driving and you are charged to 80 % So you are running miles in Hybrid mode with charging. Running currently 68% EV on my Prime - So out of 100,000 miles I really only used the battery for 68,000 miles. My guess will be a battery replacement about 150,000 miles for me or about 8 Years. I can live with that. Charge mode is not efficient, as I ran my tests and found that I get 42-45 MPG in charge mode and 55-65 in HV. Charge mode is only 75% as efficient as HV mode. But the EV mode makes the Prime so much fun, so who cares if I break the battery. By then a new EV will be out and I will replace the battery and give the car to one of my kids. If I can get 309,000 out of 1999 Camry the Prime will last that long with battery replacement. Unless another deer runs into me. Blue
So charge at home or where ever unless arriving from a long trip... I am amazed at all the free/open places to charge.
While you're all debating, I bought myself this. With few batteries from my lawnmower, I'll be finally finaly able to charge anywhere...
I will conclude this thread & all of its input with this thought: For me personally, if I could buy a future Toyota Prius Prime (or any great EV) that had a built in option that would allow the owner to add an extra ~100 lbs suitcase sized battery pack for greater range in the hatchback area, I would REALLY be interested in that option. Rob43