The dangers of high mileage EV use… Battery replacement!

One of the folks that I like to read often is Tom Moloughney’s blog (Aka Electronaut One) and he’s been writing about Battery Capacity loss and giving some hints on how to help mitigate it. As many readers know, it would seem that I am one of the higher mileage Active E drivers. I’m currently a little over 30,000 miles in a little over 14 months. And I find it hard to follow some of his advice as I tend to have to drive the mileage that I do and can’t really get to where I’m going comfortably if I decide to only charge to 80% SOC, so… I don’t. Regardless, the dangers of high mileage EV use is Battery Replacement! So at a little over 30,000 miles these past 14 months and change on the EV portion of my hybrid garage.

Some of the things to consider as we’re nearing the second month of samples of my Volt inspired sample of my hybrid garage. In my initial month, I did approximately 85% Electric vs. 15% Gasoline. This past month so far, I’m closer to 70% Electric vs. 30% Gasoline and a lot of that was because I decided to be a little more Rage Sane than Range Insane to my drive to Morro Bay.

Regardless. If folks decide to look deeper into my samples, they would notice that I haven’t driven my approximately $0.20 to $0.25 per mile BMW X5. This was originally because of choice than anything else. I didn’t really need to haul anything larger, pick anyone up at the airport with lots of luggage, or just feel “bigger” than the rest of traffic. So, the car sat at the garage. Well. It’s a nearly 12 year old car. A couple of weeks ago, I figured to start it… And Lo and Behold, it wouldn’t start. The battery was dead. The last time I bought a battery was less than six years ago, but one of the dangers of running a hybrid garage is IGNORING your ICE vehicles. Granted, this was the same challenge when my HOV capable vehicle was a Honda Hybrid Civic. But that car was not nearly as fun to drive as ANY of my BMWs. So, I drove the X5 a little more than we do now.

The Morro Bay drive went convertible top because the weather was ideal for it. We could have easily spent more money and gone with the X5 because we were headed into Santa Barbara and Central Coast Wine Country and could’ve opted to have space for a few cases, comfortably.

Regardless, the battery died. It had to be replaced. Luckily, the last replacement still had nine months left on its warranty and we got a 9/72 partial refund on the older battery to make our replacement approximately $120 after taxes. Basically the refund covered $17 of a totally brand new battery.

This experience has gotten me thinking of Tom’s write up and battery replacement in general. Tesla has just released an enhancement to its service and repair program that includes an enhancement to the coverage of the battery pack. They’ve already spelled out the cost for the 60 KwH and the 85 KwH battery packs ($8,000 and $12,000 respectively, I believe.) The Nissan Leaf’s battery capacity warranty has been spelled out in terms of what to expect over time and mileage I believe. i.e. 80% SOC on year 5 or something like that.

BMW i needs to do the same thing for the battery packs for the i3 and i8 when the cars are released or even slightly before the release of the car. As Tom champions, I second the motion. Potential purchasers of the i3 (of which I continue to hold on to hope that our second EV will be, though that Fiat 500e sure looks aesthetically pleasing to me… even though the Fiat does remind me of a gumdrop, but I digress,) will need to be able to compare EVs to each other. However as the aforementioned Tom Moloughney wrote, the Fiat 500e and the i3’s battery systems are identical, so I don’t really need to compare these specific cars (unless there’s a change in how each company regulates the temperature of each vehicle.) for what the expected battery loss figures would be. It’s not just EVs that lose capacity/capability as it ages, ICE cars also lose power as the cars age. That’s just entropy in action. It’s just front and center to EVs. I don’t necessarily like to lease my cars, regardless of what fuel motivates it. I would much rather own it outright and just pay for the things that keep it moving.

So, barring such information on battery replacement from most manufacturers, it would just be the responsible thing to do to put away some of the “gasoline savings” aside into a fund for a rainy day. Whether one save approximately $10,000 (the figure between the two Model S published numbers) or less is entirely dependent on the EV owner’s resources and ability to save. I think that it is prudent to put aside half of what a future EV buyer saves on gasoline toward purchasing a replacement battery pack in the future. I didn’t come to this number through ANY analytical means, just a guess, if you will.

4 thoughts on “The dangers of high mileage EV use… Battery replacement!”

  1. Hi Dennis,

    Nice post and thanks for mentioning me here. I do want to point out a couple things though. You wrote “the Fiat 500e and the i3′s battery systems are identical” and that isn’t entirely correct. The battery cells are the same, and are made by Robert Bosch Battery Systems, but the BMS (battery management systems) are definitely not the same and that is very important. The BMW will play a major role in the long term life of the battery and BMW has been working on the i3’s BMW for over four years now, refining it to the point of where they believe it’s the very best BMS on the market. Fiat on the other hand begrudgingly put the 500e together rather quickly without years of validation because they are only making a couple thousand 500e’s for California compliance and really isn’t interested in making EV’s (They’ve said this publicly many times). While I also like the 500e, and would consider leasing one or 2-3 years, I’d never buy one because I doubt it’s engineered well enough to last a long time. For that matter I wouldn’t buy an ActiveE either because it too was put together quickly without years of rigorous validation for this short term trial lease program.

    Also the $8,000 and $12,000 replacement cost for a Tesla battery is only valid after owning the car for 8 years, you cannot claim it earlier. SO if you drive a lot of miles and burn up the battery in 6 years you cannot get the replacement pack for another 2 years unless you pay full retail for it which will be at lease double the cost. Just food for thought 🙂

    1. Tom,

      I’ve learned a lot from you and I feel that your meticulous record keeping is a lot better than my “estimations” on experience. I was trying to compute the 8% loss that you’ve mentioned in 45,000 miles on EF-OPEC and I’m guessing mine is approximately the same at approx. 30,000 miles in near perfect California weather. (My halfway charge near the office now is at a SOC of between 45-47% when it used to be 49-53% in pretty much the same 50 or so miles a day.)

      Thanks for clarifying those points. As you know, I DO drive a lot. Not as much as you do, apparently, but a decent amount, nonetheless, so I’d gladly learn from your experience. As for the Fiat battery info, that’s a great point (regarding BMW’s engineering, etc.) and I am sorry to misquote. I’m not as technically inclined on EV technology, but learning at my 14+ months of experience. As for purchasing the Fiat 500e, their fairly unfriendly response to my request to charge “at the dealership” that I intend to purchase a Fiat 500e (which is slightly closer than the BMW dealer I currently charge at during my work day) will probably be the undoing of my desire to pick one up. Most days I will need to plug in while I’m at the office and their refusal to let their own customers use their chargers will steer me away from them. This is of course contrasted with Glendale Nissan’s installation of a CHAdeMO charger across from the BMW dealership in Glendale. As with the i3, probably a moot point if the better half doesn’t get more enthused by the aesthetics of this vehicle.

      I am hoping that Tesla’s new battery warranty
      “Except in the cases of a collision, opening of the battery pack by non-Tesla personnel or intentional abuse (lighting the pack on fire with a blowtorch is not covered!), all damage is covered by warranty, including improper maintenance or unintentionally leaving the pack at a low state of charge for years on end. The battery will be replaced at no cost by a factory reconditioned unit with an energy capacity equal to or better than the original pack before the failure occurred.”
      will help, if not, I better save MORE than the $10k reserve that I recommend to new EV drivers for battery pack replacement. Really, I may not mind leasing my next EV IF there was no mileage limit (like what we have for the Active E). However, even the “great” deals that Ford is espousing has mileage limits that you or I would laugh at.

      Thanks for the feedback and clarification.


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