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One EV weakness that needs to be overcomed, NOW!

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Old 01-21-22 | 11:01 AM
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Default One EV weakness that needs to be overcomed, NOW!

There is one weakness that must be overcomed for EV's to succeed. I'm not talking about battery packs, I'm not talking about charging times or infrastructure, nor am I talking about range. In areas where EV's are being adopted in large numbers, battery tech continues to evolve, charging times are getting less and less, range has begun to hit 500 miles plus, charging infrastructure is growing day by day. Current battery packs are built to last the life of the car, which is in the hundreds of thousands of miles, people with 8 year plus Tesla's are reporting they have only lost 4 to 5 percent battery range. So what is this problem that needs to be overcome? Dependence on 12v Lead Acid batteries.

When you pop the frunk (for ICE cars like our Ioniq that were repurposed as an EV, the hood), you will see something very familiar, a smaller version of the lead acid car battery that you see in traditional ICE vehicles, except in an EV it's called an Accessory battery. In fact it pretty much works on the same principles. I won't get into all the technical details, but it starts up the EV, powers the ECU and all the electronic accessories including AC/heater, interior lights, turn signals and pretty much everything electronic except the motors. This same battery is also used in Hybrids. The 12v Accessory battery looks something like this:



Teslas have them, Leaf's have them, Ioniq's and Prius...I could go on and on. So what's the issue with them? When they die, and many of them do, your EV becomes a brick. Your door locks won't work, lights and dash will flicker like the cars gone insane, and best of all, it won't start. If it happens while you are driving, your car will go into Limp mode, will limit your speed and you will have to pull over to the side of the road as soon as it's safe. We experienced it last year in my wife's Ioniq, it happened when my wife got off of work, the car wouldn't start and after awhile it just died. Hyundai replaced the battery the next day and everything was back to normal. Luckily, if you jump the car with jumper cables or if you have a portable 12v jump starter (I bought one on Amazon for $60, it's only the size of a portable battery) you can jump start the EV like an ICE and drive it until you replace the 12v Accessory battery. Also luckily they are not that expensive, they run about $120 and are easier to change then a traditional car battery because they are lighter. Also the ones that fail usually do so during the warranty period.

OK, with all the juice from the main battery packs, anywhere from 38 Kwh to 115 Kwh and even being fully charged, why does the car die when the accessory battery dies? Why can't it just pull juice from those fully charged main battery packs? Well, it's complicated, but here is the explanation found here: https://www.caranddriver.com/feature...olt-batteries/

IMO, reliance on a 12v lead acid battery is kind of silly and frustrating design decision, I am not sure why EV auto makers went with this design. But its something they really need to overcome. Anyway, at this point its more a minor annoyance, but one automakers need to address
Old 01-21-22 | 11:06 AM
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Everyone should own a portable jumper. Most come with jumper attachments and USB / Micro USB ports. I actually have two. I keep a Yaber in my car, and I have a Halo at work

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Old 01-21-22 | 11:10 AM
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Originally Posted by Hoovey2411
Everyone should own a portable jumper. Most come with jumper attachments and USB / Micro USB ports. I actually have two. I keep a Yaber in my car, and I have a Halo at work

https://www.amazon.com/Lithium-YABER...s%2C103&sr=8-3

https://www.amazon.com/HALO-Bolt-Com...NsaWNrPXRydWU=
Yep, I have two of them as well. They can jump any car, and are small enough to fit in the glove box
Old 01-21-22 | 11:21 AM
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Don't see how this is a relative weakness vs. a gas car same thing will happen to it battery is flaky or dies your car dies. It would be better to go with a 48 volt system but 12 volt electronics have been refined over decades such a system would be very expensive due to everything having to be redesigned or new.

BTW Tesla is phasing out the giant lead acid 12 volt battery.

Old 01-21-22 | 11:30 AM
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Originally Posted by LeX2K
Don't see how this is a relative weakness vs. a gas car same thing will happen to it battery is flaky or dies your car dies. It would be better to go with a 48 volt system but 12 volt electronics have been refined over decades such a system would be very expensive due to everything having to be redesigned or new.

BTW Tesla is phasing out the giant lead acid 12 volt battery.

https://www.youtube.com/watch?v=fJH1r1s8B6Y
The reason I'm saying its a "weakness" is they tend to die sooner than an ICE. Last year the 12v battery failed in my wife's Ioniq after 6 months. Hyundai replaced the battery and said it was probably a defective battery, but I hear this happens quite a bit
Old 01-21-22 | 11:33 AM
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Originally Posted by AMIRZA786
The reason I'm saying its a "weakness" is they tend to die sooner than an ICE. Last year the 12v battery failed in my wife's Ioniq after 6 months. Hyundai replaced the battery and said it was probably a defective battery, but I hear this happens quite a bit
What is the technical reason the 12 volt battery in an EV dies sooner? Seems like it would last longer since it doesn't get stressed by a starter motor and the voltage can be precisely maintained via the high voltage battery. Maybe I'm missing something.

Tesla dumped the lead acid battery for cost and space reasons more than anything.
Old 01-21-22 | 11:41 AM
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Originally Posted by LeX2K
What is the technical reason the 12 volt battery in an EV dies sooner? Seems like it would last longer since it doesn't get stressed by a starter motor and the voltage can be precisely maintained via the high voltage battery. Maybe I'm missing something.

Tesla dumped the lead acid battery for cost and space reasons more than anything.
I don't know, I was watching a discussion on this on Munro Live, and he was stumped by it and even more stumped that a lot of EV's still use the lead acid battery. I'm guessing it's more stressed then we know, as in the winter it has to run the heating system, fans and defrosters, wipers etc. I'm glad Tesla is getting away from lead acid. There are some people changing out their lead acid with Lithium Iron batteries. There's a brand that's highly recommended, I can't recall it right now

****EDIT****

Its a company called LIFEP04: https://www.power-sonic.com/batteries/lithium/
Old 01-21-22 | 11:53 AM
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Originally Posted by AMIRZA786
I don't know, I was watching a discussion on this on Munro Live, and he was stumped by it and even more stumped that a lot of EV's still use the lead acid battery.
I hope Sandy was not stumped by this he's an engineer with decades of experience the reasons are very apparent.
I'm guessing it's more stressed then we know, as in the winter it has to run the heating system, fans and defrosters, wipers etc.
Same thing happens in an ICE car it has the very same components. The heater in an EV is not powered by the 12 volt system* (not to be confused with the HVAC fan) that is a resistive element powered by the high voltage battery (and may be combined with a multi-valve heat/cooling pump system).
I'm glad Tesla is getting away from lead acid.
Don't know what took them so long on the flip side I think they are the only ones so far that did it.

* not 100% sure need to be fact checked on this


Last edited by LeX2K; 01-21-22 at 11:56 AM.
Old 01-21-22 | 11:56 AM
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Originally Posted by LeX2K
It would be better to go with a 48 volt system
The problem with a 48 volt system is that it takes up more space due to the larger battery, probably enough to eliminate the frunk of any EV.
Old 01-21-22 | 11:57 AM
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Originally Posted by LeX2K
I hope Sandy was not stumped by this he's an engineer with decades of experience the reasons are very apparent.

Same thing happens in an ICE car it has the very same components. The heater in an EV is not powered by the 12 volt system (not to be confused with the HVAC fan) that is a resistive element powered by the high voltage battery (and may be combined with a multi-valve heat/cooling pump system).

Don't know what took them so long on the flip side I think they are the only ones so far that did it.
I think he was stumped by the fact that EV makers still use a Lead Acid battery, I'm sure he knows their weaknesses
Old 01-21-22 | 11:57 AM
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The new 2022 Tesla models will have Lithium Ion 12V batteries going forward. No more lead acids anymore for Tesla.
Old 01-21-22 | 12:01 PM
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Originally Posted by EZZ
The new 2022 Tesla models will have Lithium Ion 12V batteries going forward. No more lead acids anymore for Tesla.
Hopefully all EV automakers go this direction, as I know the Hyundai Ioniq 5, VW ID4, and other automakers still are using Lead Acid. I'm sure my Polestar uses one, I haven't opened the cover in the frunk to check yet
Old 01-21-22 | 12:06 PM
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Originally Posted by Motorola
The problem with a 48 volt system is that it takes up more space due to the larger battery, probably enough to eliminate the frunk of any EV.
You gain way more back by being able to use high gauge wire.

Old 01-21-22 | 12:18 PM
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Originally Posted by Hoovey2411
Everyone should own a portable jumper. Most come with jumper attachments and USB / Micro USB ports. I actually have two. I keep a Yaber in my car, and I have a Halo at work

https://www.amazon.com/Lithium-YABER...s%2C103&sr=8-3

https://www.amazon.com/HALO-Bolt-Com...NsaWNrPXRydWU=
AAA/CAA works for me. they will change the battery on the spot to a whole new battery in case it will not longer work. I think that service is amazing.

Last edited by Toys4RJill; 01-21-22 at 12:24 PM.
Old 01-21-22 | 12:52 PM
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Originally Posted by LexsCTJill
AAA/CAA works for me. they will change the battery on the spot to a whole new battery in case it will not longer work. I think that service is amazing.
I have AAA as well, but it's still a handy tool to carry a portable jumper. USB makes it that much better that I can charge devices too if I need. I've also been a good Samaritan and jumped a strangers car in a store parking lot before. So it is useful. Mine also have on/off so the jumper doesn't deplete when not in use



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