DIY Electric Car Forums banner

1 - 20 of 35 Posts

44 Posts
Discussion Starter · #1 ·
Anyone have news on this? I read somewhere that Chevron lost in its attempt to squash ebasys and take the NIMH patent so it has reverted back to ovonics.

is this true? anyone have news on this?

Kinda moot now anyway. Lithiums are the king of the hill and lighter in weight to boot. Cheaper too. Go figure. NiMH should never have been allowed to be squashed. Too little too late for NiMH. Damn, good technology too but we just move forward not backwards.

Pete :)

44 Posts
Discussion Starter · #3 ·
Nimh is superior to lithium in every way that matters.

in fact today lithium is flat out not viable. period. the "cost per mile" is just too high. it will never save you a single penny over gasoline.

if your BUYING a $30k car either way OK it can save you some money (maybe) but if your buying a car TO SAVE MONEY its just not viable.

There are 3 factors that determine viability of a battery pack.

Range per charge
Total Lifespan

Size and mass are important ONLY if they exceed your limits. neither applies to nimh or lithium since both are viable for size and mass as has been proven in multiple production vehicles with both technologies.

Ranger per charge. Lithium wins BUT NIMH is "good enough" and if we use the Nissan Leaf as an example NIMH is actually superior !!

Total Lifespan. Nimh hands down. Lithium is 5-8 years 10 on the outside. nimh is proven in the real world to a projected lifespan of minimum 20-25 YEARS for the average driver.

Cost. Nimh $4500 Lithium $10,000.

When you factor all these together lithium can not touch a NIMH pack. the only way to make the leaf pack for example VIABLE against a NIMH pack would be to get that leaf pack down to $1200 a pop without compromising any capacity or features.

thats not likely to happen anytime soon.

NIMH could put usable affordable 100mile range EV into the hands of consumers right now for $13,500

Lithium can even get down to $30k without a $7500 rebate.

with the $7500 rebate the NIMH car would be a $6000 note which means your monthly bank payment would be LOWER than your currently likely spending on gasoline (I spent $125 a month and I get 52mpg in a metro!)

its essentially a car that would cost you nothing over what your spending right now.

Nimh is quite literally the ONLY viable battery tech we have right now. sure lithium IS likely the future bit its way in the future yet (at least 10-15 years) they could be rolling out NIMH cars in 6 months if we made them do it. the tech is all done and off the shelf.

Rav4EV drivers are getting 80-110 miles a charge and thats with a ZERO optimized chassis !

do an aluminum and plastic chassis with slightly better aero and you could easily keep the low end number above 100 miles to a charge. do a 4 door mid size sedan and I bet you could average 120 miles a charge.

thats enough for 90% of us.

Never said NiMH was a bad battery. But the cost right now to produce them is higher than lithium. They do last a good long time but not at full capacity. That 25 year life is not at 90% or better but more like 70% in that time. So to is lithium a good long life battery. You have no idea how long it will last. The NiMH battery is not rated at 3000 cycles but has proven to live that long but not all do. Charging is another matter too. Much more complex than lithiums (LifePo). I am not sure but one of the problems of NiMH is the commodity prices of Nickel. That is what keeps these at a high price. No one buys an electric car to save money, nor does one actually buy any car to save money. They buy one to get you from here to there and if one costs less to do so then you get that one or you buy because you like it. No car is ever purchased to pay back. I am doing electric to clean up the air and to keep the money here in our country as long as possible. I do not think the leaf is going to get better mileage with a NiMH battery and it is a known fact that lithium is a much higher density battery. So for size and weight lithium wins. Did you know that the EV1 was chock full of batteries. Not much room for any thing else. The leaf can carry 5 passengers. Way better. Just as quick and just a good of mileage and a pack much smaller.

Your argument does not hold water but large format NiMH should have never been allowed to be squashed by big oil. It is good and could have been in use with electrics all these years but nooooooooooo. Now it's lithium. Like it or not. Go try to buy a NiMH pack that will power your vehicle to 100 miles at freeway speeds for less than lithium. You will not be able to. Also NiMH batteries do not like being used in parallel so that is a problem too. Lithiums can be run in parallel and you can build a pack. I am going to be running two 100 AH packs of 120 volts each for my VW Bus. Easy to do. Simple to care for and long lasting. I will continue to use lithiums.

NiMH is a toxic battery too. Nasty stuff inside. NiCad is worse, NiFE is a good choice too. Long lasting. These batteries are also lower in voltage per cell than lithium too. Another set back to the new kid on the block. Lithium batteries are also not new technology but LiFePo is a new mixture and one that is very stable. Not so with NiMH.

Pete :)

6,276 Posts
Hi Nerys,

The NIMH patent was what? - 1989 at the latest - it's public domain now anybody can make them
(patents last 20 years - MAX)

Nobody is making them? - maybe they are not so good after all

1,148 Posts
Nimh is superior to lithium in every way that matters. ...
Total Lifespan. Nimh hands down. Lithium is 5-8 years 10 on the outside.
LiFe cells haven't been around long enough to know for sure.

nimh is proven in the real world to a projected lifespan of minimum 20-25 YEARS for the average driver.
Huh? Prius NHW10 NiMH batteries (mostly 1998-1999) started failing about at about 10 years lifespan. And that's at only 40% DOD (SOC 40-80%). Granted, they work hard, with 15C or more discharge and perhaps 12C charge; in an EV they would get an easier time of it (say 3C max).

What NiMH products have shown a 20+ year lifespan? They'd have to have been built before about 1991. The GM EV-1 started in 1996; if there were any Impacts still running (1990), then that would be coming up to 21 years.

I still consider NiMH an excellent battery and one that will live a good long time and has an excellent shelf life. I have no doubt. Toyota has decide to continue with the NiMH battery in the and the choice is a sound one. I'd love to see some nice larger format cells produced and sold to the open market. But I think it is more an issue of selling to the open market vs any thing else. As a business, would you want to compete in the open market with the new lithiums? Think your business would survive? Maybe if the prices were substantially lower than lithiums. Problem is that the prices are not that low. It is an economic problem and not a battery problem. Nickel batteries have a proven track record like lead acid and they are very robust and long lasting. Still the Lithium has more cycle life than the NiMH battery if measured at 80% DOD. NiMH are rated at about 1000 maybe a bit more and most of the LiFePo are rated at about 3000 or more. Cycle life is an important consideration and knowing how the lithiums are built and how the NiMH are built I have no doubt that the LiFePo batteries will prevail in large and small formats.

Pete :)

Don't get me wrong, NiMH batteries are a very very good battery and one that I'd love to have but since I have lithiums I will stay with them. Time will tell.

44 Posts
Discussion Starter · #8 · (Edited)
The patent expires 2014 or 2015 IIRC

The batteries are RATED to 250,000 miles to 80% DOD from the manufacturer.

Real World testing shows this to be conservative. Very Conservative.

Toyota tested one to 300,000 miles with virtually zero degradation in battery life.

There are RAV4EV's on the road today with over 150,000 miles on the original 10 year old batteries with ZERO measurable degradation in battery life per cycle. (IE holding as good a charge today as they were 10 years ago)

Lithium flat out can't touch that. not even close. I hear A123 is working on some fast charge lithium cells that have INSANE cycle life (something like in a car they would last the average person 40 years or something like that or 14,000 cycles) but they are NOT marketable yet and they are TRULY insanely expensive. ie no point if no one can afford them ehh?

The Prius is a bad example. its not a PRIMARY battery its a very small batter pack and its abused hard. as you all know the larger you make them the better they work.

so if you were to try and make a NIMH pack out of D cells well its not going to work as well as the ovonics pack would. not even close.

smaller the cells the more critical flaws are.

On top of that FIND ME ONE 100 mile range 20-25 year lifespan Lithium pack for $4500 or anything remotely close to that?

the closest we have is the leaf battery at $30,000 (3 of them to last 24 years $10,000 a pop)

GM and Ovonics succeeded and getting the retail price of the E95 nimh pack down to $4500. you just can not touch that price versus life versus performance with any other battery.

thats roughly 1.8 cents a mile if I did the math right. for the Lithium leaf pack the cost is 10.4 cents a mile.

Night and day difference.

and this assumes the battery pukes at 250k (which we already know it won't even the 80% DOD from ovonics is proving modest!!)

If I can get say 120miles a charge on an ovonics nimh (not hard especially for my commute of 54 miles) I can run that battery down to 50% DOD and still have the range I need to get to work with a 6 mile safety buffer.

whats that ? 400,000 miles? 450,000 miles?

the leaf can not even get 100 miles except under VERY optimal conditions. its typical range is looking to be more like 75 miles so it would BARELY be enough for me even when brand new.

I applaud nissan. they really did something amazing with the leaf but its not viable. you can never save a penny driving a leaf.

a good cheap econo box with the E95 CAN be made for full retail $13,500 no subsidies. that car would be virtually free FROM DAY ONE. paying for itself from day one.

1,296 Posts
Don't get me wrong, NiMH batteries are a very very good battery and one that I'd love to have but since I have lithiums I will stay with them. Time will tell.
I tend to agree.

I still like several aspects of NiMH over Li options ... but several Li options have their strengths as well ... a good system designer will look at the pros and cons of a specific battery and determine what is the best fit for a specific application.

The best I've been able to find for purchase for NiMH ... each of these are from a different battery ... no one battery is the best at everything.

  • ~$382 / kwh ( a very hard target for Li types , extremely few Li types are this cheap )
  • ~108 Wh / kg ( Many types of Li can do significantly better )
  • ~1,258 Wh / L ( I do not know of any purchasable Li types of batteries that can beat this number )
  • ~17C Discharge Rates ( there are a few types of Li that can do significantly better )
  • ~8C Charge Rates ( There are a few types of Li that do better during the CC charging phase , or during short bursts , the CV phase significantly slows down the top end of the Li family )
  • ~75% SoC after 3 years ( I do not know a Li type of battery that can do better than the LSD NiMH in self discharge rates )
  • Abuse tolerance ... NiMH in general are significantly more forgiving than Li types to being treated poorly ( this becomes less and less relevant each year as good BMS become cheaper and more available... thus these types of treatment issues become easier and cheaper to avoid entirely. )

All that having been said ... Wh / kg is the elephant in the room for any mobile application ... as long as Li types carry a significant margin in this one aspect I would expect NiMH to continue to shrink in market share and in rate of research investment ... its a major factor ... NiMH still has it's strengths and will continue to be the best fit for some specific applications ... but with significantly lower Wh / kg numbers ... those applications will see fewer and fewer mobile applications.

44 Posts
Discussion Starter · #11 ·
Can you please supply the source of your information.
I typed a lot. the sources what what exactly? most of it is easily found on google. ie its hard real data not "made up" data.

the only thing not "hard data" in my post is the $13,500 price tag so I will assume you mean that. IE data for how we can make a 100+ mile range EV for $13,500 full retail.

so here goes.

I can walk into a Nissan dealsership right now and buy a car outright brand new 2011 for around $9000.

Now take all this.

Engine - Tranny - entire cooling system - entire exhaust system - entire fuel system all the way to the tank - entire emissions control system - alternator air pump etc.. etc.. etc.. and all the fluids all of this consumes.

take ALL of that and throw it in the garbage.

full retail how much is left? my best guess those components are roughly 80% the retail value of that car. SO to be very very conservative lets say 50% to keep it simple (this means more profit too)

so our "glider" full retail is $4500

We know the battery (E95 Nimh pack) is also $4500 full retail (pure coincidence on the price match here)

so we are pack to $9000 (again not cost FULL retail price MSRP on the floor)

you can buy an electric motor for around $2000 the same for the controller around $2000

figure $500 for the charter. thats another $4500 (I know its eery all this stuff being $4500 $4500 $4500 but thats the numbers)

thats $13,500 FULL RETAIL PRICE MSRP on the show room floor NO subsidies no tax brakes Full retail with profit.

now add in the $7500 rebate and you have a loan note of $6000. if you put ANYTHING down even $1000 you greatly reduce this even more but lets leave it at $6000

thats $100 a month plus interest. even BAD credit is not going to be more than $125 especially if we have government regulatory backing to prevent abusive interest rates.

average person would be paying between $110 and $120 a month for their payments.

what do you spend in gas each month?

do this car in aluminum and plastic (give another $1000 buffer for this) you only add a few dollars to each payment but now you have a car that is rust proof corrosion proof with a drive train that is darned near maintenance free. with a battery that will last 3 times longer than the average lifespan of a car (9 years)

its win win win all around unless your #1 auto maker #2 oil company or #3 government.

to show how much of a GAME CHANGER this would be to the entire nation. the impact is simply STAGGERING.

consider UPS paid a Million bucks to design software to route around left turns. IE all right turns as much as possible.

#1 faster. #2 safer #3 uses less gas.

they were a bit shocked to find themselves saving 3 million dollars in gas the first year alone!!

now the $3 million saved in gas was not a big deal to me. Here is what I GOT out of that enlightenment.

Wait just one minute. if they saved $3 million JUST avoiding left turns.


THAT is what I got out of it. when you realize how much of every dollar we spend goes to GAS its mind boggling. earth shattering mind boggling just how much of our infrastructure is DESIGNED around gasoline.

and now you know why no one in power wants anything BUT gasoline or "some other" fuel they can control at the "pump"

Imagine if UPS converted to all electric. imagine if they PLASTERED all of their massive loading centers with solar panels to "offset" the power used to charge those trucks.

Just imagine the implications of that to UPS. now imagine the implications of that NATIONWIDE.

inside of ONE generation we would be 100% free of foreign oil. if we go HARD CORE we could be foreign oil free inside 10 years.

the savings to all of us as a whole would be staggering. mind blowing. it would be the single largest transfer of wealth and power "BACK" to the general population in this history of this nature short of its inception to begin with.

the potential is mind blowing when you REALLY sit down and think about it.

and before people say but wait your just transfering the cost and pollution back to the power plants.

this is not true. individually yes but nationally it takes MORE ELECTRICITY to put a gallon of gas into your car than it takes to put 20 miles of range into a battery pack (20mpg average)

an electric car even one as inefficient as a tesla roadster takes 283watts per mile including charging losses from the grid.

If I said it takes 5,000 watts per gallon of gas to get it into your tank I think I would be dead wrong. I think its WAY WAY more than that.

just think about the resources required to get gas into your fuel tank. ALL the resources that have no analog in an electric car infrastructure.

you will see quickly that even 20,000 watts a gallon is probably too low.

1,296 Posts

44 Posts
Discussion Starter · #15 · (Edited)
Data for cycle life at 80% dod. My source is around at best 1000 give or take a bit.
that is right from ovonics 10+ years ago. they projected 80% DOD after 250,000 miles. (divide that by 12,000 miles average driving a year to get years of life)

toyota tested to 300,000 miles with almost ZERO degradation no where near 80%

cycle of 1000 would be an utterly worthless battery pack that would only be good for 10,000 miles. I do that in 3 months. average person would have to replace such a battery EVERY SINGLE YEAR.

tell that to the rav4 owners with 150,000 miles on their 10 year old NIMH packs with ZERO loss of miles per charge so far.

maybe for NIMH AA and I beat that easily I have nimh AA's with over 2000 cycles no loss in capacity noticeable so far over 12 years old some of them and I beat the heck out of them (15 minute charges)

also I think DOD is the wrong term?? not sure.

here is what they claim essentially. the battery will hold 80% of its rated "charge" after 250,000 miles.

this means if you could go 100 miles with a new battery after 250,000 miles you might only go 80 miles per charge. 80% after 250,000 miles.

1000 cycles is nothing. such a battery would be worthless.

I can do a nice conversion for $20k and it's viable. I'd love to know where you can get large format nimh batteries of 200 ah or better for under $5 k

Get the facts to support your claims then post. Otherwise it's just blowing hot air. Lithium is king of the roost.

44 Posts
Discussion Starter · #17 ·
Lithium is worthless. too expensive too short a lifespan.

maybe in 10 or 15 years we might have better lithium tech (maybe sooner from the rumors I hear out of A123)

this data is right from GM and Ovonics. Go read your history. Stay away from MSM they won't even admit the EV1 ran on NIMH's they always bring up the RUSH first 2 years where GM shoved Leads into them because the NIMH's were not done yet and they won't give but a name mention to the rav4EV

YOU do some research. GM announced they had succeeded with the ovonics nimhs. their objective was to make a viable battery pack that would cost less than it costs to "replace" a gasoline engine and last as long as a gasoline engine. IE 200k and $4500

they did it. they announced it.

Toyota tested one to 300,000 miles before releasing the rav4EV

this is all actual historical data not fairy tales.

900 of those cars (ev1) were driving around the roads. they crushed every one of them and disabled the ones not crushed for museums and they had to sign contracts to NEVER put them on the road.

go ahead suck down the revisionist propaganda. I prefer to fight.

I can not save money with a lithium ion pack. Period.

the BEST deal is the leaf pack at 100 miles $10,000 8 year lifespan (if your lucky could be as short as 5 years but I think it will last 8)

Average person goes 12,000 miles a year so about 96,000 miles lets call it 100,000 miles (I think thats being VERY generous but lets go with it)

the car is $32k battery is $10k so the car is $22k or 10k more than it NEEDS to be.

so the "extra" cost in this car is (over a 40mpg nissan at $9550) $22,450 PLUS INTEREST which will be rather significant being it OVER $30k MORE than the nissan (including interest)

the base is $9550 (cost of the nissan)

TOTAL FUEL COST to drive the nissan for the next 8 years averaging 12k a year

$7225 plus $500 finance charges so $7725

total cost OVER the nissan for the LEAF lets pretend you have solar and pay NOTHING for electricity.


so right now after 8 YEARS the leaf is IN THE HOLE $21,950 and remember this assumes FREE ELECTRICITY and NO ROAD TAXES.

but now 8 years later another $10k for the battery. lets say they manage to get it down to $8000

so another 8 years goes buy (already had the car 7 years LONGER than the average person keeps a car)

so we take the $21950 and add $8000 for a new battery so $29950

for the nissan another $7225 in fuel but no lets pretend gas is $6 a gallon now just for fun.

$15,000 in gasoline and lets add some maintenance charges since the car is getting a little older now and our of warranty for 6 of these next 8 years.

so $4000 to be VERY GENEROUS

so $19,000 in fuel and maintenance.

lets pretend the leaf requires NOTHING no paid electricity or road taxes and NO maintenance at all (it likely would NOT require any drive train maintenance)

So 16 years goes buy your still driving the leaf FOR FREE remember NO electricity charges are in this equation.

your STILL $10,950 in the hole !!! after 16 years. even if you factor in the $7500 rebate the nissan owner can NOT get your STILL in the hole nearly $3500 dollars after 16 years !!!

it just can not work. the car is just too expensive and the battery does not last long enough.

it would take something like 20-22 YEARS just to break even and this assumes no road taxes NO electricity and NO maintenance.

it CAN NOT break even. it can never save you one penny over a gas powered car. (remember the criteria was to save money)

now if your already GOING to buy a $30k and your decided between the $30k gas car and the $30k electric car.

OK now it makes sense. but your also in an income bracket where you don't really care about the price of gas either compared to how the BULK of us who can not afford a $30k car of any sort care about the price of gas.

a NIMH powered car would PAY BACK the very first month you owned it over even the CHEAPEST car we can think of.

The one you already own.

will lithium eventually be superior? I doubt it. I think it will always cost more. I think maybe some lithium super capacitor derivative might be superior one day but chemically lithium just does not work so well at least as we know it today.

again this could change. I hear rumor that A123 has a battery that would have enough lifespan to last the average driver 41 years or something like that and it charges in 10 minutes if you have the power trunk to do it.

but its INSANE expensive and I have not confirmed that rumor yet.

there will also be LITTLE funding for such things unless they can be done cheaply because the people with the money (car makers oil companies governments) DO NOT WANT that kind of long lasting tech. its "too good" for taxation and profit.

44 Posts
Discussion Starter · #18 ·
BTW we don't need 200ah

we need 100 miles. thats it. thats what we need to be VIABLE. which is why the LEAF was designed around 100 miles. because THAT RANGE is VIABLE for 90% of the population.

its enough to let us START CONVERTING AND SAVING 25 miles to 35 miles (the filthy crap called the VOLT a slap in the face to anyone who knows anything about electric cars and GM's history) is not.

but not at $10,000 for 8 years.

10 years
250,000 miles
divided by 12 = 20,833 miles per year
divided by 365 = 57.07 miles per day

Easy breezy for lithium.

Show your work show your source. I showed and posted the link to one of many sources for NiMH batteries.

250,000 very shallow cycles. Not 80% DOD cycles.

So for a 200 ah pack of lithuim LiFePo's lets say gets you down the road to 130 miles and your at 80% DOD. Which is more than possible.

Lets say a conservative 2000 Full Charge Cycles from max full to max empty.

Now lets calculate that into total miles in 10 years.

130 miles per day with one 80% DOD charge.
365 80% Charge discharge cycles + 47,450 miles per year
at that rate we get 5.47 years of full charge discharge cycles once per day for a total of
256,000 miles.

Yes Lithiums can do that. So you average 12,000 miles per year and that equals to about 20 years of driving. Who owns a 20 year old Rav 4 that is still going strong.

Lithiums can do the dance and over the life of the lithiums the price is less than if you used lead acid by far.

Again, Where can you buy a full sized pack of NiMH batteries for less than the lithiums and that can do better in the full charge discharge arena. You can't.

So no matter how much you like NiMH they are actuality unobtainium and the matter is MOOT

Pete :)

It's moot. You can't get them. If you want to make them and have them then by all means do so. They are good batteries. That is no doubt. Never was a doubt. Better than lithiums. Don't think so.

6,276 Posts
Ovshinsky invented and patented the NiMH battery and founded Ovonic Battery Company in 1982. General Motors purchased the patent from Ovonics in 1994

Where do you get the patents expire 2014?
The initial patent was 1982 - expired in 2002

Improvements may have been patented but the original NIMH is public domain - and has been for nearly ten years!

Only the patents taken out in the last few years before the GM purchase are valid

There is a significant lag between patent and manufacture - with something like a battery about 5 to 10 years because you need to solve all of the manufacturing issues

Any battery technology that was commercially available in 1994 is now almost certainly public domain
1 - 20 of 35 Posts