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.