Who decides when a battery is degraded enough 4 warrenty?

The issue of battery degradation over time -- admited by Nissan to be as much as 30% in about 100K miles IIRR (and the inevitable big hit on resale value, or $10,000 plus to replace the pack) has been widely discussed on EV sites.


Mitsubish warrents the battery 8 years or 100K miles.
For me the 100K is moot. No way I'd put on more than about 70K miles in 8 years,
so my warrently is "8 years."
Here's MY question:


So you get out near 8 years, you're under 100K miles but for whatever reason (hot climate, hills, you got a substandard battery, or whatever ) you're only getting 50 mile range on your MiEV .. a car nominally claimed to have a 100 mile range and used to have a 70 mile range.
Who gets to decide if your expensive-to-replace battery is covered by warrenty?
What are the criteria? Is an aged degraded battery going to be excluded as "normal wear" or some such?

Alex

acensor said:

Who gets to decide if your expensive-to-replace battery is covered by warrenty?

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Mitsubishi Motors

acensor said:

What are the criteria? Is an aged degraded battery going to be excluded as "normal wear" or some such?

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The i-MiEV warranty states:

"The Vehicle’s Main Drive Lithium-ion Battery is covered for defects in material and workmanship for 8 years or 100,000 miles, whichever comes first.

Gradual capacity loss of the Main Drive Lithium-ion Battery based on time and usage is NOT covered under this warranty. See your Owner’s Manual for more information regarding Battery capacity loss."

Apparently, Mitsubishi can test each of the battery pack's cells at least to some extent. I assume that if all cells have lost capacity fairly uniformly, this would be considered normal wear and tear and thus not covered under the battery pack warranty. However, if one or more cells have lost significantly more capacity than the other cells, I would argue that these cells are defective and their replacement should be covered under the battery pack warranty. Whether Mitsubishi would agree to cover the replacement of some subpar cells under warranty remains to be seen.

So far, I have not read about anyone experiencing a noticeable i-MiEV battery pack capacity loss. However, by far, most i-MiEV's and their rebadged cousins have been sold outside the U.S. Only a few of these owners participate in this forum, so unless battery pack capacity loss had affected a significant number of owners, I probably would not know about it.

I think we all agree: we just didn't know exactly what we bought. New technology still needs to prove itself. MMC's silence and lack of needed information make me believe that even MMC doesn't know exactly what to expect regarding battery lifespan and degradation. In worst case they know and they don't want us to know. :evil:

I participate or follow many european forums and so far no bad experience was noted. It's not surprising after only few years on the market.

My battery lifespan anxiety goes down with low EV price (16.140€), high gas price 7,7 USD/gallon and even 10 USD/gallon in some EU countries, high yearly mileage (more than 20.000 miles) so my Break Even Point comes in less then 3 years, lack of mechanical skills...

I didn't really understand the battery degradation issue fully when I pre-ordered the car, but I knew what I was getting into before I signed the final papers, having read various articles, forum posts, and the disclosure documents themselves. Generally speaking, batteries don't just up and die. Over time, they take less and less of a charge. Degradation is a little steeper from a brand new state, so more range is lost over the first 5 years than the next 5. The expectation in the aggregate is about a 20% loss after 5 years, and 30% total loss after 10 or so. If you take the EPA's pessimistic 62 mile range for a new i-MiEV, that would work out to about 50 miles and 44 miles, respectively.

As I've noted elsewhere in this forum, I think EV manufacturers' discussion of range is far from frank and honest, and I fear that more than a few buyers of both Leafs and i-MiEVs have not familiarized themselves sufficiently with the technology's limitations (I don't mean to be snooty, but it does seem a bigger problem with Leaf owners, based on some of the reactions I've read in their forums to the whole Arizona fiasco). I'm particularly annoyed with some of the "are you a good candidate?" calculators, which base recommendations on a comparison of your daily commute with the range of a new EV. Nowhere have I seen those exercises include a factor for typical range degradation over 5 years, which would seem to me the minimally honest thing to do.

For my part, I decided that a vehicle with at least 30 miles range would remain quite usable for my purposes, so I signed on for the ride because nothing that I've read suggests the i-MiEV won't retain at least that for as long as I'm likely to own it. It works for me, and most criticisms and arguments don't really move me, because I didn't buy it to save money or save the earth - I bought it because it's well suited to the short distance commuting and local running around that I do, and I find EVs fun to drive.

Don't think the warranty covers the slow loss of capacity of the battery at all - We signed an agreement of some sort to this effect when we bought the car

Until/unless the battery develops a bad cell, we're not going to get anything from Mitsu even if the battery eventually degrades to 50% of it's original capacity . . . . which in theory isn't supposed to happen. The warranty covers a 'malfunction' (bad cell) but not the 'natural' loss of capacity that all Lithium cells experience

Like Vike, I went into this knowing that one day the car's max range would decrease to 40 or 45 miles . . . . I can live with that

Don

I don't disagree with any of the comments above. The question in my mind is how does one determine that there is gradual battery degradation? For example, I think we all agree that higher speeds (+50 MPH) will result in lesser range than speeds at 30-35 MPH. One will notice that when a full charge to 16 bars is done after use of the vehicle at speeds over 50 MPH results in RR being less than if the full charge to 16 bars being done after driving at speeds of of 30 to 35 MPH. In other words, HOW one drives affects range. If one drives in the same manner and achieves RR of let us say 90, then the next full charge is 80 RR, is this a sign of battery degradation? How does one detect gradual degradation? I keep accurate records of my RR, and wonder how I will know that degradation is happening. Are there any other indicators other than RR? Thanks for any input. Bill Thompson.

BillThompsonMIEV said:

How does one detect gradual degradation?

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this is quite simple. Look how many kWh is needed to recharge the battery from empty to full charge. For new one you need a little more than 17 kWh. RR is not important here.

Vike said:

For my part, I decided that a vehicle with at least 30 miles range would remain quite usable for my purposes, so I signed on for the ride because nothing that I've read suggests the i-MiEV won't retain at least that for as long as I'm likely to own it. It works for me, and most criticisms and arguments don't really move me, because I didn't buy it to save money or save the earth - I bought it because it's well suited to the short distance commuting and local running around that I do, and I find EVs fun to drive.

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Thanks Vike, and all who replied to my post.

Hey Vike, I wonder if there isn't really a BIT more to your choice of the MiEV than it being well suited to your driving pattern and fun to drive? After all for quite a bit less cash up front there are some gas cars (maybe Honda Fit, others) that would suit your pattern, are, IMO at least, fun to drive, and have the obvious advantage of you could far more easily use them for those 4 times in the year when you might want to drive more than 75 miles one-way. And as we here probably know even if one puts on lots of miles it's questionable if (after the likely depreciation hit from battery degradation and newer probably longer range EV's appearing in dealer showrooms and/or facing $10K battery replacements) an EV _really_ will save money. Could you be a bit more earth conscious than you admit? Or like what a great conversation piece an EV is?

Alex

BillThompsonMIEV said:

...... I keep accurate records of my RR, and wonder how I will know that degradation is happening. Are there any other indicators other than RR? Thanks for any input. Bill Thompson.

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Hey folks, please educate me: What's "RR"?



Alex

acensor said:

Hey folks, please educate me: What's "RR"?

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RR= Range Remaining.

The way we'll know we are having battery degradation issues is that the RR will be less after a full charge. But better would be the actual miles driven on a full charge. Because RR and trip mileage are not displayed simultaneously, it's hard to measure how well the RR estimate meets reality. Except in cold weather, I've been pretty happy with it. In cold weather, WITHOUT using the heat, I find RR is a bit optimisitc. So, I wonder if an older battery might react the same way and give an optimistic RR but leave you short on the road.

danpatgal said:

The way we'll know we are having battery degradation issues is that the RR will be less after a full charge. But better would be the actual miles driven on a full charge.

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No - Neither of those numbers would tell you anything about the battery losing capacity as it ages

RR is a computer generated number which is based on HOW you drove the car for the last 15 or 20 miles . . . . nothing else. If you did 75 MPH on the freeway for 20 miles, pulled into your garage and recharged the car, your RR on a brand new fully charged pack might be 45 miles, while if you had driven 25 MPH for the previous 20 miles and recharged, the RR on a fully charged pack might be 100 miles or maybe even more. Neither of those numbers can tell you the condition of the battery

While it's true that eventually both of those numbers will be lower, the difficulty of seeing anything meaningful on the RR dial was basis for Bill Thompson's question . . . . how will be know? It won't be by looking at the RR number, nor will the 16 bars of the 'gas gauge' tell you anything. Even measuring the amount of juice you put into the battery won't tell you much, unless you knew how many Kwh recharging from zero RR used to take vs how much it now takes 50,000 miles later

In short, what you'll probably notice first is that your same round trip to and from work now leaves you with less juice left over than it used to . . . . and even THAT is still dependant on HOW you drove those miles

Don

I wrote the following before reading Don's post, which I completely agree with.

Whoa! Before we get carried away like the Leaf community which has created its own paranoia: I defy anyone at this point in time to be able to assess whether their iMiEV battery has lost capacity. The RR display is merely an indicator of how you drove previously - at full charge, my own RR has varied from the 40's to the 90's (with a brand-new car). I wouldn't put any stock into RR as an assessor of battery capacity.

Regarding the subject of this thread, for my naive self, I'm totally unconcerned and don't even consider it worthwhile talking about. I haven't seen any evidence of any iMiEV battery degradation whatsoever and I'm quite content to see what develops in a few years' time and how it will be handled by Mitsubishi.

My 2002 Gen1 Honda Insight had a ten-year 150,000-mile battery warranty and Honda replaced the battery at nine years and ten months for free, no questions asked. Even if they hadn't, third-parties can rebuild that battery pack for less than even minor engine work on an ICE.

I'm presuming that we, as prudent EV drivers, are doing our share to prolong the life of our batteries by not abusing them.

To both Don and JoeS:

I appreciate the comments. I was hoping there might be a "canary in the mine" signal that says the battery is degrading. I guess there is no canary. I am extremely pleased with the MIEV at eight months of ownership. I drive it as conservatively as I can, and enjoy the results. I am definitely a right side of the road driver. Let the SUV's pass me, and I catch up with them at the next light. I do avoid the expressways, however; plus 50MPH sucks out too much "juice". Bill.

BillThompsonMIEV said:

Let the SUV's pass me, and I catch up with them at the next light.

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. . . . and you'll pass them up at the next gas station :lol:

The battery *should* degrade by 20 or 25% over the warranty period - As Joe mentioned, if we need another battery 7 or 8 years from now, it will probably not cost too much to either buy a better one outright, or get a quality rebuild of the existing pack. It's certainly nothing to lose sleep over. If it turns out the packs are falling apart after only 50K or so, likely Mitsu will step in and make things right - We are 'proofing' this car for them and they won't want the negative reputation a bunch of failures would garner them

Don