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Discussion Starter · #1 ·
The big news this year and last when it came to G1 Volts was the occasional failure of the main battery, and the inability to get a replacement without spending thousands of dollars from an separate provider. Just this month, a Ford EV had the same problem --- it also had no Ford-supplied replacement option --- another battery would cost thousands. My question is .. if the main battery dies and cant be repaired for a reasonable cost, can the Volt be "set" to run on the gas engine only supplying the electricity for the life of the Volt or is the car too complicated for that? Thanks.
 

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Keep in mind the battery is a portable generator, not just a fuel storage tank.

The Gen 1 Volt can be propelled at full performance by the larger electric motor MGB, described in Wikipedia as a 111 kW motor. To function at full performance, the motor needs a source of power capable of providing it with electricity at the ~111 kW level (DOE testing says the 2013 Volt can accelerate from 0 to 60 mph in 10.2 seconds by pulling a peak power of 111.9 kW from the battery). The Gen 1 Volt’s ICE can be clutched to the smaller motor MGA, which it cranks as a generator capable of ~55 kW output.

Would the Gen 1 Volt motor be capable of accelerating the car to traffic flow speed at an acceptable performance level when the traffic light turns green if the fuel supply was limited to a generator output capable of only 55 kW?

Or do you really NEED the output power generating capability of a working battery?

Similar analysis of the Gen 2 Volt: The Gen 2 Volt blends the operation of the two motors (87 kW, 48 kW) to achieve full performance in Electric Mode. Let’s ignore the car’s ability to use the ICE as a sole or even primary source of extended range propulsion. Testing says the 2016 Volt can accelerate from 0 to 60 mph in 8.4 seconds in Electric Mode by pulling a peak power of 131.1 kW from the battery. If propulsion was limited to one motor while the other was cranked as a generator, would the Gen 2 Volt’s 87 kW motor be able to accelerate the car to traffic flow speed at an acceptable performance level when the light turns green if the fuel supply was limited to a generator output capable of only 48 kW?
 

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The quick and correct answer is no.

Expensive battery pack replacements and calendar based battery degradation, are the reasons that an EV is only a right choice for those who drive a lot of miles (or are rich & don't care about money).
 

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If GM (or Ford) is no longer selling remanufactured batteries, the only options left are aftermarket or junkyard batteries. Which are still expensive - up to $10k from GreenTec for a battery with a 3 year warranty. I’m glad to have gotten mine replaced in 2021 for $9,500 (which seems a lot more reasonable than the $23k some have gotten quoted), but still that is rather steep.

I really wish there were a way to keep these Volts on the road forever. But I know the chance of someone coming up with a solution to keep these alive 20, 30 years down the road is close to zero.

Sad day, indeed. I just hope my battery hangs in there another 2 years - what good is the GM Reman Parts warranty if no batteries are available?
 

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"Fits in the same space" when the space itself is weird, plus there's nontrivial (though reverse-engineerable) signalling and control stuff to work up.

The real problem is "how much does that cost?" GreenTec is already doing the cheapest option and there's no point in anyone trying to replicate what they're doing for less than $100 cheaper than GT is charging. Anything else is going to cost more, perhaps significantly more, when the cells alone are likely to cost $5000 retail and we haven't even reached the point of the work to build the thing.

The point is that once you're up to spending $15-20k for a replacement battery for a 10 year old car, you're getting into the point where twice as much money gets you a 0 year old car, with all the improvements a decade of work can add.
 

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400v DC is 400V DC. Maybe somebody can figure out how to make the Volt work with another 400v battery that fits in the same space.
That's the trivial part of the problem. The major problem is rewriting the software so that the Volt will use that replacement battery. For example, the Volt software monitors the voltage of individual cells and bricks the car if there's an anomalous voltage reading from any cell. If your replacement power pack doesn't give the monitoring software exactly what it's looking for, the computer will brick the car. And then there's the issue of charging the new power pack. The replacement power pack has to be compatible with the Volt's software or the Volt won't allow it to be charged. And these are just the two problems I can think of off the top of my head. Also, I doubt that GM would allow anyone access to the source code to rewrite the software (because of intellectual property issues or the fact they could be liable if the car caught on fire due to faulty software). In short, I don't think replacement batteries are going to happen.
 

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So far the best price I found for a gen 1 volt battery replacement is the besthybridbatteries.com for 5,600 plus installation which should be about 500.

So for between $6000 and $7,000 you can get a refurbished battery with a 3-year unlimited warranty.

Even with pessimistic projections that's a better value than buying a new car. Given how reliable to he volt is otherwise.
 
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I wish GM had designed the Volt with the ability to bypass or lock out a bad section of the battery. Sure, you would lose one third of the EV range, but at least it would still be drivable.
 

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I wish GM had designed the Volt with the ability to bypass or lock out a bad section of the battery. Sure, you would lose one third of the EV range, but at least it would still be drivable.
You'd loose either a third of your voltage or a third of your amperage. This would also put the car into a reduced power mode.
 
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As much as I dislike government regulations, I suspect the solution for this will be a Law (not regulation as that can be changed by the next President) that states that EV batteries must be repairable and individual segments or cells replaceable. The trend has been to non-repairable battery packs, and even Tesla's anticipated structural pack appears to be non-repairable.
 

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jivefive99_2654,

The answer is yes and no, like a diaper it depends. If the battery or any other EV component fails eg battery, controller, BCM, transaxle and they shut and the EV system then no, you have a brick at that juncture. There is no torque converter or other traditional transmission in a Volt or most other PHEV or hybrid cars. The electric motors are your transmission, there is no way around that part of the design. GM chief engineer Tim Grewe explains how both Volt generations work:

The big news this year and last when it came to G1 Volts was the occasional failure of the main battery, and the inability to get a replacement without spending thousands of dollars from an separate provider. Just this month, a Ford EV had the same problem --- it also had no Ford-supplied replacement option --- another battery would cost thousands. My question is .. if the main battery dies and cant be repaired for a reasonable cost, can the Volt be "set" to run on the gas engine only supplying the electricity for the life of the Volt or is the car too complicated for that? Thanks.
 

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As much as I dislike government regulations, I suspect the solution for this will be a Law (not regulation as that can be changed by the next President) that states that EV batteries must be repairable and individual segments or cells replaceable. The trend has been to non-repairable battery packs, and even Tesla's anticipated structural pack appears to be non-repairable.
That's the thing: NOBODY IS STOPPING YOU from doing those things now. People ARE doing those things now.

What we/they are bitching about is that it costs a lot of money. And no law is going to change that. Only scale of manufacturing can.
 

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And, again because it never ends up anyplace else, this is what the Ultium platform is supposed to be able to fix: You won't have to replace a whole battery, that only exists for one model of car, that goes out of new manufacture as soon as the model of car stops being made. Ultium is supposed to be a Forever Platform, able to be replaced easliy(-ish) down to a single module that represents 1/12 of a typical car's upgradable capacity if any single module fails, that's interchangable across all GM EVs, updatable and upgradable. You'll be able to get new modules as long as there's Ultium cars being made and a MUCH larger pool of cores for refurbishment.

Heck, I even expect it to be ABLE to do that "lock out a failing module" trick*, or at least that the idea had gotten serious discussion. Because we're finally AT phase three for EVs for GM, with now decades of experience look at the problems that have been had. That's where doing things is important. "Build a better battery" isn't challenging in the same way as "how do we not have to replace a $30k part in a $30k if it fails under warranty? Let's see if we can do it for $3k or something instead" then deciding "Maybe we can sell consumers on not having to replace a $30k part after the warranty is done, too."

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* Yes that's completely speculation on my part. But it's been a question in my mind for a long time, and I haven't even seen press ASKING if that could be done, even though it's obvious to all the OWNERS that it would be a critical advantage and a huge booster of confidence in the platform versus Other EV Manufacturers Who Don't Do Modular Batteries.
 

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Discussion Starter · #15 ·
Keep in mind the battery is a portable generator, not just a fuel storage tank.

The Gen 1 Volt can be propelled at full performance by the larger electric motor MGB, described in Wikipedia as a 111 kW motor. To function at full performance, the motor needs a source of power capable of providing it with electricity at the ~111 kW level (DOE testing says the 2013 Volt can accelerate from 0 to 60 mph in 10.2 seconds by pulling a peak power of 111.9 kW from the battery). The Gen 1 Volt’s ICE can be clutched to the smaller motor MGA, which it cranks as a generator capable of ~55 kW output.

Would the Gen 1 Volt motor be capable of accelerating the car to traffic flow speed at an acceptable performance level when the traffic light turns green if the fuel supply was limited to a generator output capable of only 55 kW?

Or do you really NEED the output power generating capability of a working battery?

Similar analysis of the Gen 2 Volt: The Gen 2 Volt blends the operation of the two motors (87 kW, 48 kW) to achieve full performance in Electric Mode. Let’s ignore the car’s ability to use the ICE as a sole or even primary source of extended range propulsion. Testing says the 2016 Volt can accelerate from 0 to 60 mph in 8.4 seconds in Electric Mode by pulling a peak power of 131.1 kW from the battery. If propulsion was limited to one motor while the other was cranked as a generator, would the Gen 2 Volt’s 87 kW motor be able to accelerate the car to traffic flow speed at an acceptable performance level when the light turns green if the fuel supply was limited to a generator output capable of only 48 kW?
And so there is no way (wouldnt work anyway) to bypass a broken battery and use just the gas engine, you are saying?

The Volt does run normally when it is just the gas engine and the main battery is dead.
 

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Discussion Starter · #16 ·
The quick and correct answer is no.

Expensive battery pack replacements and calendar based battery degradation, are the reasons that an EV is only a right choice for those who drive a lot of miles (or are rich & don't care about money).
Hope not. The Federal Govt is of the mind that everyone is gonna be in electric cars .. whether we like it or not.
 

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Discussion Starter · #17 ·
If GM (or Ford) is no longer selling remanufactured batteries, the only options left are aftermarket or junkyard batteries. Which are still expensive - up to $10k from GreenTec for a battery with a 3 year warranty. I’m glad to have gotten mine replaced in 2021 for $9,500 (which seems a lot more reasonable than the $23k some have gotten quoted), but still that is rather steep.

I really wish there were a way to keep these Volts on the road forever. But I know the chance of someone coming up with a solution to keep these alive 20, 30 years down the road is close to zero.

Sad day, indeed. I just hope my battery hangs in there another 2 years - what good is the GM Reman Parts warranty if no batteries are available?
Since no one is gonna wait for 1-4 hours to charge up a battery, there will have to be some type of quick-replace swap-out battery standard in the near future that you can buy at any "former gas station." Similar to propane tanks.
 

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And so there is no way (wouldnt work anyway) to bypass a broken battery and use just the gas engine, you are saying?

The Volt does run normally when it is just the gas engine and the main battery is dead.
The battery isn't DEAD when it's discharged and the engine turns on. It's just used as a buffer into which power from engine and braking can go, and from which power for zippy acceleration comes from, and (if it's convenient) rotational power from the engine can be fed to wheels to move the car along. But between that 25 and 30% of charge or whatever it is, the battery is VERY active while the car is in use in hybrid mode. A broken battery can't do that, so... no more car. (COULD Chevy have designed it differently? Probably. Did they? No. And we have to live with what was done, not what could have been. That, too, was A Thing That Was Learned, but it may be moot unless GM decides to do Voltec hybrids again someday.)
 

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EV batteries must be repairable and individual segments or cells replaceable. The trend has been to non-repairable battery packs, and even Tesla's anticipated structural pack appears to be non-repairable.
Hence the design of the Ultium battery as hellsop discusses above: 1) a standard battery component across all GM EV's = LOTS more availability for replacements, 2) designed to allow new battery modules/tech to be used even with wildly different chemistry, not just those made when the car was built. These two alone would address the Volt battery issues we are seeing had the Volt been built on the Ultium platform (that did not exist at the time).

Just like GM learned from the EV1 when it created the Volt with it's range extender, it learned from the Volt when it started on the Ultium battery platform. That's how progress works.

I was talking to a potential EV buyer and told them the issue with batteries seems to be a 10-12 year lifespan and scarcity of Volt replacement modules. That I would hold off and seriously look at an Ultium-based car. And yes, others like Tesla are going in the opposite direction and simply saying you need an entirely new pack, $25k (or whatever) please.

The Ultium approach is more where I'm at. Of course if you don't keep cars longer than 10 years, you probably don't care.
 

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Hence the design of the Ultium battery as hellsop discusses above: 1) a standard battery component across all GM EV's = LOTS more availability for replacements, 2) designed to allow new battery modules/tech to be used even with wildly different chemistry, not just those made when the car was built. These two alone would address the Volt battery issues we are seeing had the Volt been built on the Ultium platform (that did not exist at the time).

Just like GM learned from the EV1 when it created the Volt with it's range extender, it learned from the Volt when it started on the Ultium battery platform. That's how progress works.

I was talking to a potential EV buyer and told them the issue with batteries seems to be a 10-12 year lifespan and scarcity of Volt replacement modules. That I would hold off and seriously look at an Ultium-based car. And yes, others like Tesla are going in the opposite direction and simply saying you need an entirely new pack, $25k (or whatever) please.

The Ultium approach is more where I'm at. Of course if you don't keep cars longer than 10 years, you probably don't care.
If GM really does pull off the interchangeable/module replaceable ultium battery they can use this as a huge marketing item over Tesla and anyone else who isn't doing this. I hope they do - I'm looking at the Equinox EV as my Volt replacement down the road.
 
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