Batteries, being chemical reaction devices, will NEVER magically overcome TEMPERATURE.
They might get 'better', but consider this:
When you had a cordless drill that ran on nickel-cadmium rechargeables, it would work in extreme cold and hot... just not as well as if ambient temps were moderate. As we progressed to NiMH, we got more power from the same package size, but it became important for the charger to keep a close eye on the battery whilst charging, so it didn't exceed the chemical reaction's 'safe' range. As we moved to Lithium-Ion, we got even more, however, it was not just charging temperature, but operating temperature that needed limitation, and not just in high, but also low temperature, which is why my cordless tools are totally worthless on a jobsite unless it's betwee 40F and 78F... they cannot be expected to operate OR CHARGE unless within that range.
Electric vehicles are no different in all respects... energy density, charging and discharging rates- all part of the challenge. Add on the fact that besides being extremely expensive, chemical storage batteries are large, and extremely heavy... take your lightweight economy car, remove it's 400lbs of aluminum engine and gasoline tank, and put 3000lbs of batteries and 300lbs of electric motors... yeah.
Cold is a double-thick club- not only is the battery very reluctant to respond to charge/discharge rate demands, there's a substantial additional load- the heating resistors... that take away all that precious charge without moving an additional foot down the road.
The science is simple: Take a 85lb battery, like the Trojan T-1275 Plus and measure the energy available... it's a 1.99kWh battery... that's 1990w for one hour. 742w = 1hp... so that battery is good for... 2.68hp for 1 hour, then it's done. That's 85/2.68 = 31lbs for ONE HORSEPOWER HOUR of energy.
Now consider one gallon of gasoline... that's 112,000btu/hr, or 43hp for 1 hour, per GALLON... that's 231 cubic inches, and it weighs about 6lbs.
but comparing apples-to-apples... we're dealing with an 85lb battery that's 13" x 7.25" x 10.75"... occupies 1013 cubic inches.... so...
In the same WEIGHT that the 2.68hp/hr BATTERY is...
You could carry 85/6= 14.16 Gallons... that's 609 HORSEPOWER HOURS of gasoline.
Now, in the same VOLUME as that 1013 cubic inches of battery space, you can carry 1013/231= 3.16 gallons of gasoline... that's 43*3.16 = 135 hp/Hr of energy.
Now let's do the same exercise backwards.
My son's Honda Accord holds about 14 GALLONS. That's 14*6 = 84lbs, and it takes up 14*231 = 3234 cubic inches of space... and the total fuel energy is 43*14 = 602hp/hr.
The Honda Accord gets about 26mpg between city and highway driving. Nurse it on the interstate, and it'll break 30... with range of about 350 miles.
To make that 350 mile range, it will take 224 of the aforementioned batteries...
--Or a group of TEN, recharged 23 times...
Now... each time you stop to recharge, it will take you NOT LESS THAN 8 hours to get a full recharge of the battery array.
The fuel pump providing about 5 gallons per minute, It takes less than three minutes to fully recharge the Honda Accord's fuel tank.
Now... if this doesn't put it into perspective... keep in mind that...
10 85lb batteries is 850lbs. Not only does this considerably increase the rolling load on tires, it means much more rolling resistance, and it requires considerably MORE energy to climb a hill, because it's carrying almost a half-ton of batteries. Yes, you can use regenerative dynamic braking coming downhill to apply a little 'recharge' to the batteries, but the batteries cannot be charged nearly as rapidly as the car is decending and braking.
The gasoline automobile's fuel tank GETS LIGHTER as you empty it... that means it becomes more efficient as you empty the tank. Batteries don't change much from charged to discharged.
Electric cars are neat for places where you're WELL WITHIN the range of a half-charge, where you don't have substantial heating or cooling requirements, where you have a place to park it each night with a charger.
Yeah, internal combustion is wasteful. During wintertime, we recover a whole bunch of that heat by warming up the passenger compartment. In the summertime, we lose efficiency because we're air-conditioning the vehicle, but that puts equal (actually greater) hurt on the electric car, because the internal-combustion engine is already spinning it's prime mover, adding an accessory compressor load is not a significant change in it's scheme.
Basic chemistry is incredibly difficult to beat. People look at hybrids and battery-electric vehicles like they're something 'new'... but really, they're not- electric cars and trucks existed BEFORE internal combustion... they just lost when it came to real-world operational demands.
Now let's talk about safety: When you get in a car crash, there's fuel that can burn. Shut down the fuel pump, and once the exhaust is cool, as long as there's no source of ignition, there won't be a fire... except for the battery underhood. Look at most of the motor vehicle fires, the greatest margin start as a result of the BATTERY catching on fire, or an electrical short.
Take that little battery out, and replace it with one that's fifteen times larger... and jab a steel fencepost through it. Whadd'ya think's gonna happen?
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Stan IL&TN wrote:
You don't believe Ms Cortez has it all figured out, 
how could you not believe.
