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You missed a key reason - batteries are very heavy, and to achieve the kind of range that makes it practical for drivers to switch from ICE requires specificall

You missed a key reason - batteries are very heavy, and to achieve the kind of range that makes it practical for drivers to switch from ICE requires specifically-designed chassis layout and materials to accomodate battery weight in a suitable location to maintain acceptable weight distribution With a breakthrough in energy storage technology e.g. solid state, this issue might go away, but right now it compels the production of vehicles specifically designed to be EV and relegates retrofitting to a hobbyist discipline providing relatively disappointing results in range and/or handling.

sn_master 6y ago
yup, most retrofitted cars get way less mileage than regular EVs (150 miles or less).
titzer 6y ago
I get that, but cars have gas tanks, back seats, and trunks, too. Also, the actual electric engine is very small, leaving a lot of room in engine compartments themselves. The only reason we would need very large batteries is to have a very long range, which would not be necessary if we could have removable, modular batteries that are easy to replace at (what was formerly) a gas station.
- FooHentai 6y ago
  EVa have back seats and trunks just like ICE, and they need to be usable by the vehicle owner just the same so I’m not sure I see the relevance. For retrofitting, locating some batteries in the engine bay is possible. This seems to be avoided by ev manufacturers in favour of locating a monolithic battery pack under the passenger compartment, for weight distribution, simplicity, and (I assume) safety reasons. Physically swappable battery packs isn’t feasible because of the sheer weight of the packs (a leaf 40k pack for example is 210kg). Plus each car manufacturer has different specs and shape packs. Fortunately we already have a completely fungible, extremely portable unit that can be hot-swapped into every EV at nearly any location just like petrol - a kWh of electricity. Today it takes a bit of time to fast charge, but again with visible-on-the-horizon breakthroughs in battery tech e.g. solid state, fast charge times could drop from ~30 minutes to 3.
  - titzer 6y ago
    Of course if you are designing an EV from scratch you want to put the weight of the battery low and in the center for best stability, but with a conversion you gotta find space wherever. Gas tanks are already pretty low and central for the same reason, but clearly an EV battery pack is a lot denser than a full tank of gasoline. Swappable battery packs clearly wouldn't be a single piece, as there are going to be a variety of different bays and sizes. They'd need to be smaller, portable, and stackable, like rectangles or hexagons. It's not really that hard to do if you design for it. If the batteries are under the car then a lift or underground bay you drive onto is fairly easy to do. Or you could just have a kind of dolly that slides under the car and can detach/reattach them. The fact that we never really thought in this direction seems like a blind spot. I mean, look at how pit crews for racing work. The whole car is designed to be swappable in seconds flat, and also for minimum weight and maximum speed. It's just engineering and design investment.
- yellowapple 6y ago
  As a further elaboration on this point: range becomes far less of a concern with widespread charging stations. If every parking lot was covered with solar panels and every space had a charger on it, the "range" concern would evaporate pretty much immediately for day-to-day use; just plug the car in at every stop to top it off.
  - sn_master 6y ago
    Range concern won't evaporate in the US anytime soon simply because of how far spread cities and forests are and how much people like to roadtrip, specially in the Summer. When I used to hike pre-COVID, I used to do 150 miles one-way easy, and sometimes even return same day.

sn_master 6y ago

yup, most retrofitted cars get way less mileage than regular EVs (150 miles or less).

titzer 6y ago

I get that, but cars have gas tanks, back seats, and trunks, too. Also, the actual electric engine is very small, leaving a lot of room in engine compartments themselves. The only reason we would need very large batteries is to have a very long range, which would not be necessary if we could have removable, modular batteries that are easy to replace at (what was formerly) a gas station.

FooHentai 6y ago
EVa have back seats and trunks just like ICE, and they need to be usable by the vehicle owner just the same so I’m not sure I see the relevance. For retrofitting, locating some batteries in the engine bay is possible. This seems to be avoided by ev manufacturers in favour of locating a monolithic battery pack under the passenger compartment, for weight distribution, simplicity, and (I assume) safety reasons. Physically swappable battery packs isn’t feasible because of the sheer weight of the packs (a leaf 40k pack for example is 210kg). Plus each car manufacturer has different specs and shape packs. Fortunately we already have a completely fungible, extremely portable unit that can be hot-swapped into every EV at nearly any location just like petrol - a kWh of electricity. Today it takes a bit of time to fast charge, but again with visible-on-the-horizon breakthroughs in battery tech e.g. solid state, fast charge times could drop from ~30 minutes to 3.
- titzer 6y ago
  Of course if you are designing an EV from scratch you want to put the weight of the battery low and in the center for best stability, but with a conversion you gotta find space wherever. Gas tanks are already pretty low and central for the same reason, but clearly an EV battery pack is a lot denser than a full tank of gasoline. Swappable battery packs clearly wouldn't be a single piece, as there are going to be a variety of different bays and sizes. They'd need to be smaller, portable, and stackable, like rectangles or hexagons. It's not really that hard to do if you design for it. If the batteries are under the car then a lift or underground bay you drive onto is fairly easy to do. Or you could just have a kind of dolly that slides under the car and can detach/reattach them. The fact that we never really thought in this direction seems like a blind spot. I mean, look at how pit crews for racing work. The whole car is designed to be swappable in seconds flat, and also for minimum weight and maximum speed. It's just engineering and design investment.
yellowapple 6y ago
As a further elaboration on this point: range becomes far less of a concern with widespread charging stations. If every parking lot was covered with solar panels and every space had a charger on it, the "range" concern would evaporate pretty much immediately for day-to-day use; just plug the car in at every stop to top it off.
- sn_master 6y ago
  Range concern won't evaporate in the US anytime soon simply because of how far spread cities and forests are and how much people like to roadtrip, specially in the Summer. When I used to hike pre-COVID, I used to do 150 miles one-way easy, and sometimes even return same day.