Results 1 to 2 of 2
Thread: Electric car issues
08-18-2006 05:30 AM #1
Electric car issues
Starting a new thread to deal with EV’s in order to keep another thread on topic:
From a post to the topic "Hybrid w/turbine engine":
“Thanks for all that info ex-EV1 driver!
Maybe you can clear up another issue I have with full electric cars:
Arent batteries toxic and need replacement every 5 years or so?
I thought we were no where near having green batteries.
And I thought that was the reason hybrids are using so little batteires (that and the weight... but weight is getting better with litium and the like)
And would you agree that if not using batteries, using a gas motor to generate electricity is kind of not efficient or dare I say... pointless for the future?
(cost of research, engeneering, etc... for such a temporary solution)
Also, I think converting natural gas engines to hydrogen or other gaseous fuel has been done without much modification. That could be a cheap alternative to reengeneer complete engines (be it electric or other)
Oh.. one last point I'd like to debate is the ruggedness of electric motors compared to ICE with winters or sandy / dusty places. I think ICE would produce less landfill garbage in the long run, what do you guys think?”
I think you’re pretty much on track with what I’ve been working on for the past couple of decades so let me try to share my current assessments.
The limitation (if any) of the Battery Electric Vehicle (BEV) is as you suggest: the battery.
Toxicity: Modern EV’s will use either NiMH or Li-ion batteries. Neither are toxic, hence, technically, they can be thrown into a landfill. Older, PbA (Lead Acid) and NiCAD (Nickle CADmium) batteries are toxic (the lead and Cadmium respectively) and can cause ground water contamination as well as lots of other nasty stuff. They are easy to recycle and well contained so it is economical to do so – you wouldn’t want to send to a landfill anyway.
Battery Life: Battery life is affected by time and number of charge/discharge cycles. Current batteries can last for well over 100,000 miles worth of charging and discharging and this is still improving, partially through more careful control of charging and temperature. The time issue may be an issue. My understanding is that we’re at about a 5 year battery life for Li-ion batteries. The replacement price will drop a lot with mass production but whether the market will chose to increase the life is yet to be seen. Remember that with an ICE (Internal Combustion Engine) vehicle, the water pump, alternator, and fuel pump are generally designed (obviously, I can’t prove this is by design) to fail at about the 5 year/70,000mile point. Transmissions go at ~100,000 miles Therefore, while improvement in battery life is probably possible, it isn’t clear that anyone will put much effort into it. Car companies would love a $2000 maintenance at about the 5 year or 150,000 mile point.
Today’s hybrids use so little battery because the ICE manufacturers can’t cope with the concept of the ICE being subordinate to the electric. They are putting as little electric power in as they can. More battery = better fuel efficiency.
You’re right – it isn’t hard to burn H2 in a (NG) natural gas motor. But their aren’t very many CNG vehicles in the US and why waste the energy stripping the H2 out of the NG? Fuel transfer of gaseous fuels is much tougher than just pouring liquid into a tank (or plugging in electricity).
Feasible electric vehicle technology was developed in the late 1990’s, were on the road in California, but were crushed by GM, Toyota, Honda, Chrysler, Nissan, and Ford (models: EV1, RAV4EV, EV+, Epic minivan, Altra, Th!nkcity/RangerEV respectively)
Electric motors can be extremely rugged. They expect nothing from the environment (no air), hence they can be fully sealed (immune to dust). The only possible interaction with the outside might be a bit of cooling but that can be another sealed system. Think about submersible sump pumps. The lifetime of EV’s is a whole lot longer than ICE since there is very little to wear out and no high temperatures or steep temperature gradients. A modern, brushless electric motor has only moving parts with simple bearings. An EV needs no transmission but maybe 1 fixed gearset and a maybe a differential. Braking is mostly done electronically, with friction braking mainly for emergencies and abnormal situations. There are no oil changes. Routine maintenance is only for tire changes maybe every 40,000 miles.
I don’t think you need to worry about landfill. The EV1 was over 98% recyclable but, of course, most ICE cars are quite recyclable as well.