Originally posted by: gsellis
I still think they are fools. They can void the warranty. In so doing, they have now removed themselves from any future recourse on actions that are now underway to extend the protection of battery replacements.
This is a good point.
And Li Ion batteries have a charge/discharge lifecycle just like other batteries, but not as sensitive as NiMHd, etc. Increase the usage and deepen the cycle, shorten the life span.
You don't have to deepen the cycle to increase the usage - you just add more batteries and keep the cycling the same.
Also, just running battery will increase the thermal ranges the batteries experience.
I'm not following you here - are you saying that the batteries will heat up from more frequent usage? The thermal range of the batteries in use is much smaller than the batteries experience from just enviornmental exposure (ie. drive it through Death Valley in summer, driving it through Michigan in the winter will be a much wider range than driving it around Chicago and using the batteries more frequently). At least when they are being actively used they are being thermally managed.
Add to that, improper charging of any Li battery is a risk.
There are several different types of lithium rechargeable batteries which are not prone to Dell laptop/Sony battery lithium ion explosions... they are just expensive. A123 lithium ion batteries are one example of a lithium-based rechargeable which is considered as safe as nickel-based batteries.
Smart circuits are part of the kits and should mitigate it, but you do not know everything Toyota tested. You would assume that if they work well on the battery only, Toyota would have extended the battery only operations cycle.
On the contrary, rather than my assuming that they found an engineering problem with a plug-in hybrid, my assumption is that they found an economic problem with them. The Prius battery right now is a 38-cell 7.2V NiMH 6.5Ah battery pack. This would be a ~1.7kWh battery but to ensure longevity Toyota decreases the total cycle range to something close to a 0.6Kwh battery (something like "max charge is 70% of theoretical capacity, and minimum charge is about 30% of minum charge") This is capable of driving the car for approximately 2 miles on battery power alone. Something like the Hymotion L5 increases the battery capacity to approximately 5kWh and costs about $15k more increases the battery-only range to about 20 miles (30 miles according to
www.hymotion.com... but their math doesn't make sense to me... my calculations are for about 20 miles... maybe they are driving around at a point where wind resistance doesn't matter... I can't figure it out... but 20 seems about right to me). The reason why I don't think there's a plug-in Prius... it increases the car cost from $22k (base) to $37k (base).
From an engineering perspective, electric cars were one of the first types of cars to be invented. See:
http://en.wikipedia.org/wiki/Electric_car - there's a photo of Edison and Ford in front of an electric car. There's no engineering reason that I can think against electric cars. The problem today is the same problem that they had back in the early 20th century: cost.
There is a basic axiom that covers this. There are liars, damn liars, and battery engineers (source unknown - Autoweek in the 80's).
Perhaps it's my Spock-like nature, but... I don't get it. You are saying that battery engineers are completely untrustworthy? I've seen some specifications that seem pretty far from reality, but still... batteries do work... add more to a Prius and it will go farther on electric power. Plug it in at night, and they will charge. I don't understand how any of this could be considered lying.
The other axiom is a fool and his money are soon parted. If they want to spend more on getting a new car sooner because they ran it as an all-electric, it is their money.
This, like your comment about warranties, is, IMO, a good point. Hybrid cars are expensive and plug-in hybrids are even more expensive. Batteries cost a lot of money and don't last forever.
And to think... I almost went to grad school in Ft. Collins! I could have been your first customer and maybe even helped build one of these cars. Maybe in a couple years I can buy one off you.
I don't have a hybrid or plug-in hybrid car and I've never worked on a conversion kit. As my evening hobby, I build, design, and wind my own electric motors and I have an electric... bicycle (although I'm not sure that you can call a vehicle with a 35mph top-speed and a range of about 40 miles a bicycle anymore... perhaps a "pedal-assist scooter") that I commute to work in on nicer days. The rest of the time I drive my Honda Civic (non-hybrid). I just keep up with the whole plug-in hybrid news because I'm interested and a bunch of the mailing lists that I subscribe to are more Prius-focused.
I has to shorten battery life. All batteries have a limited number of charge cycles and more frequent charging and discharging caused by using it as PHEV and likely deeper discharges will wear the batteries faster and there's no way to avoid it. It might not be too bad if they do a good job of balancing the wear accross the additional batteries added but if they do a poor job you could easily substantially shorten the life of your batteries.
I agree that if you do a poor job, then you could screw things up. But if you have battery with a life expectancy of 15 years and then you add in 10 more of these same batteries to increase the range (while keeping everything else the same) then the battery life should stay the same... 15 years.