Convert old hybrid car battery to new type battery

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dusty rose

New Member
Jun 18, 2017
3
Southern California
Hello. I have a 2007 Toyota Highlander Hybrid. It stills has original battery, living longer than most. Replacement is about $3000. I would like to put in a newer battery, but understand that it will need some type of conversion? I also have a Hyundai hybrid, 2016; the battery is smaller and cheaper to replace. Does anyone have any ideas or knowledge if this is being done with other older hybrid cars? If this post is a duplicate from earlier, which I could not find, please direct me to that forum discussion. Thank you for any thoughts or help with this issue.
 
Why is the Highlander battery needing replacement? Toyota considers their batteries to be designed for the life of the car. Usually the cost is directly related to the battery capacity and labor to replace. The Highlander is a heavy vehicle and has a larger battery because of its weight. The dealer can replace the battery if needed. If yours is kaput, check the date. There is a 10 yr warranty. At the dealer it is almost twice the cost of the Prius battery.
http://www.greencarreports.com/news/1078138_toyota-hybrid-battery-replacement-cost-guide
Are you thinking about a Roper conversion for much more capacity? That isn't cheap either.
http://www.roperld.com/science/hihyplugin.htm#HiHy
 
When the car was purchased the estimated battery life was about three years, so we bought an extended warranty. But ten years later the battery is still working. In my research it appears that most of the batteries on this car only lasted about three years. The extended warranty is also no longer valid as it has outlived it. (I have learned not so buy extended warranties) So we would like to give the car to my son but he would not be able to afford the 3k price of a replacement battery. It was not covered for life of car nor expected to work for the life of car. Since batteries have change quite a bit in ten years, I was wondering if anyone had a similar situation where they adapted a more current battery for hybrids, smaller more affordable to older model hybrids. I spoke to a person at the dealer and they said that the current batteries would not work with the hylander's computer. The car itself is in very good condition and I am sure many more years and miles.
 
Not sure where the battery life estimates came from. Neighbor has an 07 Highlander in which the battery is also still ok. Why replace? Have you determined the remaining battery capacity is very low? There is a product to restore and maintain battery health for hybrid batteries. Not sure how well it works.
https://hybridautomotive.com/collections/store

Where is the 3K replacement price coming from? The article says it's more like $6100 for the Highlander before the core charge is deducted. The dealer should replace the battery with the same, not a substitute.
 
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I agree with begreen on errors in the the battery life numbers you're relying upon. We have a 11 year old hybrid Highlander (HyHi) and the battery is still going strong. Some EVs did have some battery life issues (e.g. Nissan Leaf) related to lack of a battery cooling system but not Toyota's - at least not that I've heard of.
WRT your original question though -- I've not seen where anyone is replacing older Ni-MH batteries in earlier hybrids with more recent battery tech (e.g Lithium Ion). In Toyota's at least, the battery is highly integrated in the vehicle with electronic controls and programming. As some have found (e.g Roper), it is tough to work around those controls. The ways that batteries are used and charged is different dependent upon their chemistry.

Someone might well develop Li-ion batteries as replacements in early hybrids but these will most likely require reprogramming of the vehicle so it would likely have to be done by a Toyota dealer.
 
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My concern is the battery dying while we are on the road and the car to functioning. I have done researched have had no clear answers as to if it would continue to run gas only, at least to get it to a shop or safely out of traffic. My numbers on the years these batteries last was based on research I did a couple of years ago, many claims the batteries did not last past three years. the 3k cost was what we got from the dealer. we have also read that there is a recharging kit. Not sure about that. No the battery has no been tested, it is the age that I am concerned about and compared to what I found on internet it seemed it was living past majority of batteries out there. we want to give to my son who will have our young granddaughter in it and certainly don't want them to have a problem. the car itself has over 200 k miles. I think I will get back to the dealer and see what the current prices are for new batteries so I can be prepared. they were never meant to last for the life of the car, of course we have never found an auto dealer to be honest with us either... Toyota included. thank you everyone for all your feedback.
 
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If the battery did die th vehicle would continue to run on gas and the Energy System alarm light would light up on the dashboard.
Just to be obnoxious, wouldn't a small piece of electrical tape be in order?
I understand the old Honda Insight starter wouldn't turnover without the battery, but how about this hybrid?
 
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Just to be obnoxious, wouldn't a small piece of electrical tape be in order?
I understand the old Honda Insight starter wouldn't turnover without the battery, but how about this hybrid?
Actually from what I recall the simpler Honda Insight can go on but the Toyota system will not be able to start the motor without the traction battery having enough charge to do so. The battery has to be very low for this to happen.
 
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Actually from what I recall the simpler Honda Insight can go on but the Toyota system will not be able to start the motor without the traction battery having enough charge to do so. The battery has to be very low for this to happen.
You're likely correct. The 12v battery on the Toyota is quite small - probably too small to even start the engine.
 
I'm as proactive as the next guy but spending $3000 replacing something that's still good is silly. It has proven it's dependable, the replacement might not be. You could offer your son a new car battery or $3000 and let him decide.
 
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My numbers on the years these batteries last was based on research I did a couple of years ago, many claims the batteries did not last past three years.

There has been a lot of disinformation produced and disseminated by those with financial interests in the petroleum industry to dissuade people from buying electric cars. It sounds like you bought into some of it.

But what I want to know is why you would buy it if you thought it would need replacement in three years?
 
In the OPs defense it's not just petroleum industry 'disinformation'. The old Toyota hybrids used NiMH batteries. In consumer applications other than EVs these batteries originally had a very short lifespan of a few hundred to at most a thousand cycles which works out to only a few years. I.e:

http://batteryuniversity.com/learn/article/cycle_performance_of_nicd_nimh_and_li_ion

The hybrid car packs last much longer but I still think 10years is very good, I would not count on it going 15. The only battery types that make 20+ years are large off grid systems and telco backup batteries (nickel iron).


Re: Prius vs. Insight. One difference about the first gen Honda Insight was that it Had a very small electric motor and was Incapable of moving under electric power only. The car was designed with a backup traditional starter motor for the engine run off the 12v battery, rather than using the hybrid traction motor to start the engine. This may be why it can drive with a depleted hybrid battery.

https://en.m.wikipedia.org/wiki/Integrated_Motor_Assist#Starting
 
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In the OPs defense it's not just petroleum industry 'disinformation'. The old Toyota hybrids used NiMH batteries. In consumer applications other than EVs these batteries originally had a very short lifespan of a few hundred to at most a thousand cycles which works out to only a few years.

Correct. But the petroleum industry and their on-line shills repeat the type of information you cite above as if it applies to any and all battery/electric vehicles. The truth of the matter is that batteries in current BEV's are degrading much more slowly than conventional "wisdom" suggests. Most people will sell/trade-in the vehicle long before the batteries need replacement. In fact, data from owners of the Tesla Model S is indicating very slow degradation and that the batteries will likely last 150,000 miles or more with less than 15% range loss.

Also, the warranty is better than I've seen on cars powered by gasoline:

The Tesla Model S drive unit warranty has been increased to match that of the battery pack. That means the 85 kWh Model S, our most popular model by far, now has an 8 year, infinite mile warranty on both the battery pack and drive unit. There is also no limit on the number of owners during the warranty period.

How come no one complains that gasoline engines wear out in just 150,000-200,000 miles and manufactures have a mileage limit on the warranty? Not only do gas cars begin their life filling your garage with toxic gases, their engines wear out, start to burn oil, loose efficiency, produce more deadly gases and become less reliable, perhaps stranding you as they wear out (if they don't kill you of cancer first).

Where is the outrage about this? And we are supposed to worry about batteries that will eventually lose 15% of their range many years down the road??? Only a greedy oil company could make that sound impractical or even scary.
 
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I think the electric vehicle revolution, with battery prices falling every year, offers a huge opportunity for modders and backyard mechanics to retrofit early hybrids and BEV's with the latest technology, upgrade gas cars/trucks to electric and create very cool/capable off-road and super high performance electric vehicles. Others will focus on extending range and other capabilities. Of course this takes knowledge of the emerging technologies and a responsibility to know what you're doing and keep it safe. But that is no different from the hot-rodders of the 1950's through present. No longer do they need to know about carburetors and jets, turbo's and superchargers, etc. Now it's about charge and motor controllers, windings and magnets, wire sizes and terminals, grounds and shunts, regenerative brakes and software.

The possibilities are endless and BEV aftermarket suppliers are going to have a field day providing the latest and greatest to those modders on the leading edge.
 
In the OPs defense it's not just petroleum industry 'disinformation'. The old Toyota hybrids used NiMH batteries. In consumer applications other than EVs these batteries originally had a very short lifespan of a few hundred to at most a thousand cycles which works out to only a few years. I.e:

http://batteryuniversity.com/learn/article/cycle_performance_of_nicd_nimh_and_li_ion

Not sure what you mean by 'old'. The Prius still uses NiMH today. Only the Plug-in Prius and the post-2016 'Eco' trim uses Lithium, neither selling in large volume until quite recently. The earlier PiP actually had a Lithium traction battery AND a NiMH battery for the regen braking! Probably more than 96% of the Prii on the road today are 100% NiMH

I think this is one of the reasons that Toyota was always so weird about EVs (to the point of running anti-EV ads)...they decided that Lithium was a bad technology, had a lot of sunk cost in NiMH engineering, and knew (a la EV1) that NiMH was not really suitable for a BEV.
 
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Not sure what you mean by 'old'. The Prius still uses NiMH today. Only the Plug-in Prius and the post-2016 'Eco' trim uses Lithium, neither selling in large volume until quite recently. The earlier PiP actually had a Lithium traction battery AND a NiMH battery for the regen braking! Probably more than 96% of the Prii on the road today are 100% NiMH

I think this is one of the reasons that Toyota was always so weird about EVs (to the point of running anti-EV ads)...they decided that Lithium was a bad technology, had a lot of sunk cost in NiMH engineering, and knew (a la EV1) that NiMH was not really suitable for a BEV.
I was surprised to learn this.
More info on this here:
http//www.reuters.com/article/us-toyota-batteries-idUSKBN12U0ZH
 
Correct. But the petroleum industry and their on-line shills repeat the type of information you cite above as if it applies to any and all battery/electric vehicles. The truth of the matter is that batteries in current BEV's are degrading much more slowly than conventional "wisdom" suggests. Most people will sell/trade-in the vehicle long before the batteries need replacement. In fact, data from owners of the Tesla Model S is indicating very slow degradation and that the batteries will likely last 150,000 miles or more with less than 15% range loss.

Also, the warranty is better than I've seen on cars powered by gasoline:

The Tesla Model S drive unit warranty has been increased to match that of the battery pack. That means the 85 kWh Model S, our most popular model by far, now has an 8 year, infinite mile warranty on both the battery pack and drive unit. There is also no limit on the number of owners during the warranty period.

How come no one complains that gasoline engines wear out in just 150,000-200,000 miles and manufactures have a mileage limit on the warranty? Not only do gas cars begin their life filling your garage with toxic gases, their engines wear out, start to burn oil, loose efficiency, produce more deadly gases and become less reliable, perhaps stranding you as they wear out (if they don't kill you of cancer first).

Where is the outrage about this? And we are supposed to worry about batteries that will eventually lose 15% of their range many years down the road??? Only a greedy oil company could make that sound impractical or even scary.
You just pointed out the main reason I limited my latest car purchase to plug-in EVs. After we found out our Subaru needed an expensive exhaust repair, new head gaskets, steering rack and was due its timing belt soon, after the big valve cover gasket job we did last fall..... I threw in the towel. BEVs were prioritized over PHEVs and I'm happy witb my '17 Focus Electric so far.
 
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Like others have said it sounds like the hybrid battery in the Highlander is working fine. I looked on car parts.com - a used part search. There were many 2007 Highlander hybrid batteries. This is a good sign - it means they usually last a long time. Some parts aren't so reliable. For example, finding a hybrid battery for an early Honda Insight is more difficult and expensive because they often expire before the car does.

And if the battery does go out on the Highlander your son could get a good used one (grade A) for between $500 and $1000. It is just a used part on a car that can be replaced if it goes bad.
 
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We sell Prius and other hybrids on the side. We also rebuild Prius batteries. The 12v battery in Toyota hybrids is used to operate the computers only. The hybrid battery operates the starter for the gas motor.
I have never rebuilt a Highlander battery. They are somewhat similar to the Prius and I would expect are serviceable.(We rebuild Prius batteries for $500+/-)
That being said, I would suggest getting a used battery that has reasonable miles on it if the "red triangle of death" shows up.
I would avoid the dealer unless you are flush with money. Any garage with the high-end Snap On scan tool can diagnose hybrid issues.

There are probably shops in your area to assist. My guess is you can replace the Highlander battery for under $1,000.
OH, do stay away from used batteries from warm/hot climates. I have had two cars from down south up here in Maine.
Both had hybrid battery problems. Twice. Never had a repeat issue with New England cars that I rebuilt.
 
I looked on car parts.com - a used part search. There were many 2007 Highlander hybrid batteries.
I'm curious what search parameters you used to find the hybrid batteries. I searched at carparts.com for a 2006 Highlander Hybrid Limited and found only the small 12v "starter" batteries. Maybe your search was for a newer vehicle?

I've looked a bit and only been able to find any HEV, PHEV, EV batteries available on ebay.
 
Look under "Battery". You do need to choose Hybrid drivetrain in the window prior to the listings.
There are still going to be some 12v batteries in there.
And ask about warranty. Sometimes batteries are self discharged enough that you would have to dig into them to recharge.
Not a DIY project for many.
Buying local is always better.
 
I'm curious what search parameters you used to find the hybrid batteries. I searched at carparts.com for a 2006 Highlander Hybrid Limited and found only the small 12v "starter" batteries. Maybe your search was for a newer vehicle?

I've looked a bit and only been able to find any HEV, PHEV, EV batteries available on ebay.

semipro, here is the sight I was looking up the battery on (I live out west, but put in your region) http://car-part.com/
 
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