Battery Replacement

>Now have 96,000 relatively maintenance free miles on our 2001

(KM) Coming up on 50 K that's exactly what I want to hear!

> and have been doing some research on advanced Li ion batteries.
> Supposedly Ovonics will be making a Li ion with a higher amp-hr
> capacity than the Panasonics in our PRius. I e-mailed them about
> their production, but they indicated they would not sell to a one
> time retail customer.

(KM) Will they sell to your local dealer? Would the local dealer be
willing to install it? Ask who they sell to in your area.

> The research article indicated they outfitted a 2001 with their batteries
> and were able to drive 25-30 mile at 35 miles per hour without the
> gas engine coming on due to the current being maintained by the
> more efficient and larger ampacity bank.

(KM) That would be nice! Did they have to do anything to the
computer to get it to work with a different battery?

 

ya Lithium ion batteries are well known to be the best battery you can buy IF you can afford one. they didnt by any chance quote you a price for that battery they were talking about did they??

well, i have seen quotes for similiar batteries that have run anywhere from 10-50k. heck the 4 hour battery for my camcorder is over $100 and its a little dinky thing.

 

Well, regular lithium batteries are good in some applications, but a hard current draw from electric motors and such aren't really suitable for lithiums.

For driving electronics (PDAs, Cell phones, video cameras, etc) which have low-current requirements, Lithium is the way to go. It packs a lot of energy density into a small space, giving you a long runtime.

Perhaps they're working with a different lithium chemistry which can handle the more demanding requirements of electric vehicles.

Dave.

 

the application i saw uses multiple parallel banks to achieve the high current requirements. this no doubt contributed greatly to its high cost. but if weight is a problem (in battery applications, that is the only real drawback) then Lithium Ion is by far the best solution. its charge to weight ratio is about 175 i think. i have a chart here some wheres and cant find it right now. (charge to weight is a comparison of storage charge using Lead Acid as a base.)

but we need not count out Nickel Metal Hydrides yet. although they are still lagging Lithium Ions by a good deal, they are improving. the same guy who invented them is also working on Hydrogen technology, but he says that NiMH batteries will better than double their capacities in 5 years. so for those who want to keep their Prius long term, there may be a solution that will give you a lot more battery power.

 

How about some of the new high density capicitor storage devices? Advantages that I know of are charge to weight and no downside to deep discharge (no battery memory issues). Univ. of ID. engineering dept. went the capacitor route for their SUV for some sort of competition in Detriot.

 

hmmm dont know. not familiar with the technology. do you have a link?

i think there are several avenues that the world can go in but getting the funding and backing of major distributors has been the sticking point.

about a year ago i read an article about scientists working with micromotors. these were motors that usually measure less than a few millimeters across. they had built a small jet turbine that ran on propane. it could easily have been converted to generate electricity and they were investigating the possibilities of putting the technology to work in laptops. if sucessful, they envisioned a laptop with an endless run time because it would run on propane and be refilled just like a butane lighter.

another application was a mini refrigerator that would be used to cool laptops also running on propane. i suppose you guys would never guess that im a computer nut eh?

 

you should have, by all reports, at least another 50-90,000 miles in your current battery, why change till needed?

 

hmmm if i could replace it for a battery that will run 25-30 miles without recharging, i be tempted to replace a brand new batttery if the price is right.

 

25-30 miles

I'm not sure you're being entirely realistic here.

YES, the idea of a vehicle that can do all around-town driving in pure-electric mode while still being able to drive long distances and filling up at the gas pump is quite a desirable feature, it's more complex to add to the Prius than just sticking in a larger battery pack.

First of all, the Prius is designed to get ALL its energy from gasoline, which is definitely an efficiency bottleneck. I, more than most Prius owners would like to see a plug-in hybrid, but alas, the best solution I've come up with is the 1974 Porsche 914 in my garage that I'm converting to an around-town car with 25-30 miles range. Anyway, it wouldn't be practical to charge a Li-Ion pack w/ 30 miles range off just regen.

Second, the Prius isn't really designed to expect a large battery pack -- it kicks in the engine no matter what when you hit 41MPH (unless you're in neutral). I've heard that it has no problem utilizing a larger pack, but it may not be entirely practical. An EV-mode button would certainly help, but it'll still be kicking in the ICE more than you might want.

My recommendation to you if you are serious about this would be to investigate thunder-sky.com, which is a good source for EV-sized LiIon batteries. Some people have used them as their primary pack in a pure EV. Be warned though that LiIons can be tough to manage, nad you'll need to come up with a charging solution that doesn't cause them to catch fire.
You could always try good old lead acid, if you don't mind adding about 1/2 a ton of weight to your car (not to mention eating a fair bit of space).

-Ben

 

ummm well, if you saw the price, then you would realize that it isnt realistic. however, you would have to go to the original post and see that the OP posted a link to an article of someone who modified or is about to modify the Prius so it will do the 25- 30 miles on electric.

I would not try it since the costs are astronomical. we are talking several thousand for the battery alone. (i would GUESS $25k+) as no price was mentioned, i am guessing. but i do know that LiIon the battery king.

 

If it ain't broken don't fix it, especially if the fix wil be very expensive.

 

We're working on just this: more batteries + grid charging.

the PRIUS+ Campaign
for explanations

PRIUS+ Plug-In Hybrid Conversion Group
for technical discussions (message archive is public; read the last 2-3 dozen messages to get the picture; key files are mirrored at URL above; we're somewhat selective about who can be a member of the group

 

Apparently, adding battery capacity to the Prius is not a trivial matter. Clearly it can be done, but it's not for the weekend do-it-yourselfer. Same goes for grid charging. Lithium batteries (of which LiIon is only one sub-category) hold promise, but are expensive and require complicated protective circuitry. I will avidly devour any news of people working on this (and ultra-capacitors as well) but I think I'll wait for Toyota (or Honda, if they ever really get on the ball and go full hybrid) to do it at the factory.

Also, with a 25-mile range, I'd want better performance. In EV mode you have to drive pretty gently. So to be practical MG2 would have to be bigger, and all the circuitry more robust, and with MG2 bigger, the PSD would probably have to be heavier... and, in short, we're talking major model revision.

I think it's coming. I just don't think it's a DIY project.

 

I'm planning on going to an empty parking lot at my next opportunity and flooring it in reverse. Should give an idea of the power MG2 has by itself off the line, unassisted by ICE. I have no idea, but seems possible ECU doesn't allow MG2 to use full power (I know top speed is limited to prevent MG1 overspin) in reverse but probably is fairly close for off the line, especially since motors have identical performance in both directions.

 

Part of the limitation is the battery. It can't deliver the power the MG2 is capable of using.

 

First off don't you see issues with different battery chemistry in general?
I mean Li-ion batterys have a tendency to die, not from excessive drain, excessive cycling, or high current draw, but time. I've seen laptops that won't hold 50% of their original charge after 3 years and that's when the person uses it maybe once a month on battery. What's going to happen in environment like a car. Maybe there is different chemistry that some manufactures are using, but I'd still be wary of this.

Also, capacitor technology would be very expensive/complicated. In that world you are dealing with a steady state current storage device. You will be limited by peak voltages of maybe 5-10v and high internal resistances. Typically you can find extremely high power/weight density if you are using an aerogel based capacitor, but that becomes a very expensive solution. All of the problems with charging a capacitor could be easily solved with computer control, but it is not going to be a direct swap type of solution.

I'm also amazed at how everyone is focusing on going EV or better battery life, why not a more efficient engine design/or system management? I mean really, it's not like the technology for a non-EV 80 mpg car can't be easily implemented, by any manufacture. It's just a shame the car companies are going to milk us for all we are worth before they move to better technology.