How battery improvements will revolutionize the design of the electric car
gigaom.com
gigaom.com
I had no idea this was true. If so, that's very significant.
Also from GigaOm: http://gigaom.com/2010/08/08/how-moore%E2%80%99s-law-has-spo...
Go read chapter 9 of The Innovator's Dilemma, first published in 2000. This chapter is based on an analysis he did of electric cars. Given the rate of battery improvement he thought that a mass market affordable electric car would be viable for the mass market somewhere around 2020.
At current trends, that's not too far off from when Tesla can be expected to try to make a mass market electric car aimed at ordinary people.
We also have a petrol station on nearly every street corner, but it will take a long while for quick chargers to approach anywhere near this. There is also already a split on adapter standards, which will take time to settle down.
But that said, fuel cells that can utilize natural gas or propane would be fierce competition. That would give you better energy density, greater range, and access to fuel is already widespread. Quick charging would be solved. The only question left is the cost of ownership of the fuel cells.
The frunk would have to be specifically designed as an engine compartment, both because of regulations, and because one wouldn't want fumes to harm the passengers. (Less of an issue with hydrogen fuel cells.)
I think that's a great idea, though. Something like that would greatly increase the utility of something like a Tesla Model S. Range, in particular range in winter driving, would be greatly improved by the power generation and the ability to use waste heat for passenger compartment heating.
I find it interesting to read that:
o To get the kind of highly variable "transient response" (change in power output) required for automotive applications, the author proposes using a chemical battery as part of the power management system, as the fuel cell system can't itself respond quickly enough.
o The control system is as much or more challenging than that of an internal combustion engine, requiring control of these sub-systems:
__ * Reactant (hydrogen) flow subsystem
__ * Heat and Temperature subsystem
__ * (pure distilled) Water Management subsystem
__ * Power management subsystem
__ * If not fueled by hydrogen, an on-board fuel processor subsystem to break the chosen carbon-based fuel down to hydrogen
With just hydrogen fuel, it still takes an air compressor, three heat exchangers (fuel temp, fuel cell stack heat extraction, compressed air heat extraction), an air humidifier, a water separator, a power converter, a chemical battery (and software of course, to implement the control system) to make it all work in vehicle applications.
The problem is that we have evolution now while what we need is revolution. We need order of magnitude more density achieved without the use of rare or exotic materials.
It's fantastic that 3 of the following 10 items are improving by leaps and bounds. But if all 10 of them don't get better together, the Internal combustion engine will still be making the Tesla Model S look like a rich person's toy.
1. How much does it weigh? If it weighs too much, maxing out on all the other attributes doesn't matter.
2. Does it harm anyone if a person is in close proximity when the battery is crushed, shot, or wrecked in any way?
3. Does the lifespan decrease with prolonged usage in -40F or 150F weather? Does vibration break it?
4. How long does it take to fill up assuming unlimited power resources?
5. How long does it take to charge given roadside assistance resources?
6. How many charge-discharge cycles?
7. If you leave the car in a garage for 6 months is the battery bricked? What is the discharge rate when left unattended?
8. Cost of replacing the battery.
9. Toxic chemicals or rare metals to make disposing the battery expensive or bad for landfills?
10. How quickly can you discharge the battery without it melting or exploding?
The success of battery powered cars doesn't have to hinge on any of these items if Gasoline prices were to triple while the cost of batteries stay the same. Then battery powered cars will immediately dominate, and solar power charging stations in your roof will be the only economical choice.
2. Conventional Li-Ion (cobalt) cells are definitely dangerous, best stick with NiMH or LiFePO4 to avoid that problem.
3. Those temps are a bit extreme... arguably small markets there.
4. Newer battery tech is reducing the charging time massively... I've read more than a few quotes of ~5 minutes for an 80% charge (diminishing rates beyond that). Example (granted, not near market ready): http://www.extremetech.com/extreme/134635-scientists-develop...
5. That's a much bigger problem... towtrucks would have to have a considerable powerplant on-board for this.
6. Again, improving by leaps and bounds all the time. Just one example: http://www.a123systems.com/lithium-iron-phosphate-battery.ht...
7. Well designed controls should prevent this (shutting down the on-board systems when batteries get below a certain point, rather than taking them past the point of no return).
8. This is coming down fast enough that by the time you have to replace the battery pack, it'll be a non-issue.
9. Again, avoid cobalt-based Li-Ion batteries, and this is not an issue. LiFePO4 batteries are an enormous improvement on this problem - less toxic than the lead cells in your car now.
10. Yet another massive improvement that's a side-effect of the lowered internal resistance in modern batteries. This goes hand-in-hand with the improvements in charge-rates (lower internal resistance means less heat from current, whether going in or coming out of the cells).
Which 3 are you referring to?
Not really. The high temp is actually on the low side - a parked car in sunlight in the summer can reach 190 degrees!
-40 is a bit extreme for some parts of the world, but in other places it's not unusual. Perhaps not for the entire winter, but certainly as a daily low.
You don't put the battery packs on the inside of the car any more than you'd put the fuel tank on the inside. Typical placements are underneath the vehicle, arguably the coolest area possible. This is where the Tesla model S places the pack, as does the Fisker Karma, and this is also where the old ('97-'03) RAV4 EV placed the NiMH pack.
Or will the owner just call AAA for a tow or flat-bed to a charging station?
7. If you leave the car in a garage for 6 months is the battery bricked? What is the discharge rate when left unattended?
Unattended and not plugged in? Else, trickle charge with manual or perhaps robotic plug-in.
9. Toxic chemicals or rare metals to make disposing the battery expensive or bad for landfills?
Lead-acid batteries are generally recycled now, why not newer batteries? I would expect a battery replacement to be handled as an exchange, by specialists.
10. How quickly can you discharge the battery without it melting or exploding?
How much acceleration can the tires handle? Crashes were mentioned in item 2.
That doesn't seem like an important consideration for the vast majority of drivers.
http://www.bloomberg.com/news/2013-02-11/tesla-falls-after-n...
I have seen hotels in cold climates (Finland) provide electrical receptacles for block heaters for IC engined vehicles - which might be adequate for a slow charge, or at least for maintaining a better working temperature for a battery pack - too bad the writer didn't have access to something like that.
My takeaway is that colder regions will need denser charging station networks to serve long-distance travelers, and that all-electric vehicles will be less popular for long-range multi-charge trips in colder climates, but still good for daily commutes and any "out-and-back" trips where the vehicle can be charged at the destination while the travelers are doing something else. (meal, meeting, entertainment, overnight stay, whatever).
Tesla Motor's solutions to these problems has been:
* Many small cells. Small cells are easier to cool and you get tighter temperature uniformity.
* Active temperature control. Energy is cheap compared to the capital cost of the cells. Active temperature management earns back its own range penalty. It enables the widest choice of cell chemistry.
* Physically isolate the cells to prevent cascading failures.
* Robust battery box rigidizes the vehicle's frame.
* "Skateboard" architecture not unlike GM's Autonomy concept / Hy-Wire prototype (except no fuel cells). You get a low center-of-gravity, battery swap capability, and an aerodynamic belly for free. Pack is easy to access using a standard vehicle lift. Compatible with novel business models, like "buy the car, lease the battery".
* Fine-granularity diagnostics and charge/discharge control. Improves pack reliability, longevity, and performance.
Inside a car in direct sunlight it can reach 190 degrees.