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Chevrolet Volt Battery Pack Carries Standard Eight-Year, 100,000-Mile Warranty

The Chevrolet Volt extended range electric vehicle will provide customers with a standard, eight-year/100,000-mile (161,000 km) warranty on its lithium-ion battery pack. The warranty is transferable at no cost to other vehicle owners. The Volt’s comprehensive battery warranty covers all 161 battery pack components, 95% of which are designed and engineered by GM, in addition to the thermal management system, charging system and electric drive components.

As a quick comparison, Tesla’s battery-electric Roadster has a bumper-to-bumper 3-year, 36,000-mile (58,000 km) warranty. Tesla also offers an extended battery replacement warranty for an extra $12,000—i.e., prepaying for a replacement battery at a discount—that covers the period from the expiration of the new vehicle warranty to up to 10 years after the sale.

Tesla says that the pack in its electric Roadster has an expected battery life of 7 years or 100,000 miles.

Nissan has yet to release details of the warranty on the LEAF, but says that the warranty coverage will be “competitive”.

The Chevrolet Volt’s batteries have exceeded our performance targets and are ready to hit the road. Our customers are making a commitment to technology that will help reduce our dependence on petroleum. In turn, we are making a commitment to our customers to deliver the highest standards for value, safety, quality, performance and reliability for an unprecedented eight years/100,000 miles.

—Micky Bly, GM executive director, global electrical systems

As an extended range electric vehicle, the Volt can operate under a full range of climates and driving conditions without limitations or concern about battery depletion. It has a range of about 340 miles and is powered with electricity at all times. For up to the first 40 miles, the Volt is powered solely by electricity stored in its 16-kWh lithium-ion battery, using no fuel and producing no emissions. When the Volt’s lithium-ion battery runs low, an engine/generator seamlessly operates to extend the driving range another 300 miles on a full tank of fuel.

Key battery features include:

  • Thermal management for durability and reliability. The Volt battery can be warmed or cooled. The battery is designed to provide reliable operation, when plugged in, at temperatures as low as -13 °F (-25 °C) and as high as 122 °F (+50 °C).

    In cold weather, the battery will be preheated during charging to provide full power capability. In hot weather, the Volt’s battery can be chilled during charging. The Volt’s liquid thermal management system can also be powered during driving by the battery or engine/generator.

  • Diagnostics for safety and performance. The Volt’s battery management system continuously monitors the battery real-time for optimum operations. More than 500 diagnostics run at 10 times per second, keeping track of the Volt’s battery pack; 85% of the diagnostics ensure the battery pack is operating safely, while the remaining 15% keep track of battery performance and life.

  • Cell design and chemistry for performance and efficiency. GM’s selection of a prismatic cell design and LG Chem’s manganese spinel lithium-ion chemistry is designed to provide long life and high power output, with a properly maintained temperature. This enables better vehicle acceleration and increased regenerative braking capability for improved vehicle efficiency, GM says.

  • Energy management for durability. Fully charging or fully depleting a battery shortens its life. The Volt’s energy management system never fully charges or depletes the battery. The Volt’s battery has top and bottom “buffer zones” to help ensure long life.

GM engineers have completed more than 1 million miles and 4 million hours of validation testing of Volt battery packs since 2007, as well as each pack’s nine modules and 288 cells. The development, validation and test teams have met thousands of specifications and validated each of the Volt battery’s components.

Tests include short circuit, corrosion, dust, impact, water submersion, crush and penetration, and extreme temperature swings combined with aggressive drive cycles, also known as “Shake, Bake and Roll.”

GM’s Brownstown Township plant, which began building prototype batteries in January, soon will begin regular battery production.

Comments

HarveyD

With this wall to wall extended guarantee, it may be wise for New GM to limit the production of Volts for the first few years. Battery pack management and durability will mature within 3 or 5 years.

If future battery packs last up to 20,000 cycles, well built BEVs will last 20++ years with minimum maintenance. Will the car industry and service garages like that?

Davemart

Harvey, simply inventing future battery packs with a life of 20,000 cycles is not sensible.
Why not go the whole way to dilithium crystals?
The very best bettery we know of in respect of lifetime is the lithium titanate chemistry from Toshiba, which is good for 6,000 cycles at 15C, and perhaps, although this is not definite, 12,000 cycles at 1C.
The lithium titanate chemistry trades off the high energy densities of the MNC batteries to achieve this.
AFAIK there is no basis at all for your projections, which are entirely fanciful.

SJC

Of course they are "fanciful", everything posted on here is opinion and B.S...why do you think that they call it a Congress?

ai_vin

LOL!
Good one SJC.

Monkey

You can bet GM's warranty will require the owner to be tied in to yearly visits to an authorized dealership or the deal will be off.
My experience of such places is not great.. shoddy, overpriced work, my local grease monkey mechanic does a far better job.
Though admittedly he probably wouldnt recognise a T shaped lithium battery pack even if it fell on his head.

HealthyBreeze

I don't expect 20,000 cycles, but I guess it's possible that really good power management electronics could distribute partial discharges across the hundreds of individual cells such that no individual cell is discharged more than 6,000 or so times, but the pack as a whole is discharged 20,000 times. Lots of assumptions in that, though.

I'm suprised we're not hearing someone suggesting as an alternative 300 Kwhr Li-Air batteries that only go 100 cycles, but only have to be recharged once a month (albeit for 3 days straight).

Zhukova

I wouldn't want a battery that could be charged 20,000 times. It cost 10,000 bucks and a few years later, a new battery is available with the same capacity but half the weight and half the cost. So you're stuck with the old battery. Like my 720 line HDTV. I paid $2,000 for it a three years ago because the 1080 HDTVs cost $4,000. Now the 1080s are ony $1500 and nobody wants to buy my obsolete 720. It makes it difficult for me to buy a new 1080 tv.

The Volts' battery will probably last a long time. It's only discharged to 30% anyway. Quick charging will probably shorten its life. Personally I think the Volt is a waste of time because of its complexity. But all those parts - dual mode transmission, 70 hp ICE, battery/engine management system, will keep the parts and repair industry in business. Ford has a better idea (sorry), just go all electric. Simpler, cheaper, less risky, more reliable and practical.

HarveyD

Davemart: There are, in a few labs around the world, new electrode composition than can withstand up to 20,000 cycles. The energy density and maximum power have to be improved. The new graphene electrodes may be in that category but with potential better energy density and higher power handling capabilities. More development is required during they next five years.

Every time a PHEV or BEV goes downhill or decelerates, the battery pack is being recharged and goes thru a minor cycle. City e-taxis and e-buses, specially in hilly cities like SF, will have to withstand a multitude of mini cycles every day. They will need battery packs with many 1000 cycles. Professional power tools are having the same problem and their current batteries do not last that long but they are getting better.

Dave R

@HealthyBreeze - not sure how you plan on discharging a full pack 20,000 times but each cell only 6,000 times and expect to improve cycle durability.

Assuming you're thinking of putting appx 1/3rd of the cells through a full cycle while letting the other 2/3rd rest - that's the wrong approach.

It's full cycles which kill batteries faster, you'd be better off cycling every single cell through the middle 1/3rd of it's charge capacity. Then you get the benefits of stressing each cell 1/3rd as much during charge/discharge as well.

Which is in fact what GM is doing with the Volt and why they are only using 8 kWh out of 16 kWh capacity.

GM isn't the first - all hybrids do the same thing to manage battery life.

ToppaTom

GM ALREADY limits production.

Warranties typically tempt owners to return to an authorized dealership periodically and if you are lazy, you can - I doubt it will be required.

All cells will be cycled only ~35% (between ~35 and 70%, to reduce stress and extend live far, far beyond 3 x the life of 100% cycles.

Engineer-Poet

Micro-cycles are very easy on batteries. The NiMH packs in early Priuses did extremely well in Vancouver taxis (micro-cycles), and the test AC Propulsion did on vehicle-to-grid technology found that microcycling left its 2-year-old battery pack with a capacity INCREASE.

the doctor

saying they have a warranty is nice, but I have owned GM's before, and the only way to get full warranty service is with a gun.
without specifying the terms, saying it has a warranty is meaningless. It could be the standard "if it wont hold a charge" , which doesnt help you when it still holds a charge and only goes 10 miles. Or it could be waiting until the monitoring device decides it is no good, probably shutting it down like an ink cartridge and forcing you to replace it, or the monitor may be like apple Iphone bars, never admitting the true condition.
I dont trust GM, I have had too many of them.
The final discharge/recharge algorithm should be interesting, the initial one seemed to guarantee an average life of 6 years with half failing just over 3 years due to excessive deep cycle. But they keep tweaking it for advertising reasons, not customer satisfaction.

danm

Warranties are always full of small print. I only got about 30,000 mi out of my last tires that were supposed to last 60,000. They said I had not come in regularly to have them balanced and rotated, so warrenty = void.
-
I'm impressed that GM goes to 80,000.

Reel$$

I'm just damned angry that it's GM leading the way. Why can't it be some little outfit with big ideas and no cash?

"As a quick comparison, Tesla’s battery-electric Roadster has a bumper-to-bumper 3-year, 36,000-mile (58,000 km) warranty. Tesla also offers an extended battery replacement warranty for an extra $12,000"

If GM tried this trick they'd still be in decline. They double the mileage Tesla warrantees. Oh well, it'll be good for everyone if Volt does a decent job introducing extended range EVs.

HarveyD

Limiting charge/discharge cyles to mini cycles (35% - 70%) will certainly extend batteries life to at least 8 years at 2 cycles/day = (8 x 365 x 2) = 5840 cycles. New batteries designed by Phostec + Montreal U + Hydro-Quebec R&D Labs have been tested to 20,000 cycles and are still going on. Power handling and energy density compare with other recent lithium batteries. Future nano-graphene batteries should do much better, specially with regard to energy density and power handling capability.

Considering current and future development, 2015+ batteries may last as long as the e-vehicle or up to 20+ years.

Mariordo

I have a reservation for the Leaf (and live in one of the US initial launch markets). Today (July 16) Nissan sent a survey via e-mail with most questions relating to the battery warranty, comparing 5yr/60k mi vs 8yr/100k.

It seems GM announcement is making Nissan reconsider its strategy regarding the battery pack. There are also questions regarding how much is the buyer willing to pay to extend the battery warranty from 5yr/60k to 8yr/100k, clearly trying to establish the sweet spot for this potential charge.

In my case, I will go for the Volt if they keep the 5yr/60k, just think of the low resale value. Who is going to buy an used EV if the new owner has to buy a new battery pack that cost around $10K or that only recharges 65-70% of its capacity (reducing range proportionally)?

wintermane2000

Resale value is a HUGE issue. They say that evs will have only a 10% resale value after just a few years compared to 25% for normal cars.. And thats AFTER they get the initial prices for the things down alot.

SJC

We now start to see the issues with EVs being brought out ahead of their prime time. Early adopters will have them, but will the market continue to expand rapidly year after year?

Engineer-Poet

It's hard to see how a few-yr-old EV could have such a low resale value when

  1. the rapidly-dropping price of batteries makes pack replacement cheaper than when it was new
  2. the car would still have plenty of use in it even with a shortened range
  3. aftermarket or even homebrew replacement packs would be quite feasible.
The NiMH-powered electric RAV-4's were selling for quite a bit more than their new price, and appear to be going strong.  Such rapid depreciation is simply not realistic given the proven market for used EVs.

ToppaTom

I expect used EV prices will drop much less than for an ICE due to the battery being the only real "hidden" concern.

Before EVs become plentiful (2020?) you will just have a used one checked for battery condition - prolly EZer than a used car check of and ICE.

SJC

If a 5 year old EV wants to sell for $15,000, but it will need a new $10,000 battery in a few years, will anyone pay $15,000 for the EV?

Engineer-Poet

If a 5-yr-old EV had a $10,000 battery that now sells for $4000, what's it worth?

danm

EV's will retain their value because the price of batteries will fall dramatically and the rest of the power train will be like brand new, compared to an ICE where the engine and transmission are constantly wearing out.

ToppaTom

Oh damn danm, I was too slow.

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