Ally Major Guard EV

Don’t know where the OP read the GM specs were for "at least 80% of the new battery capacity," but that’s not what the 2018 Chevrolet warranty booklet says. All batteries lose capacity over time. Loss of capacity is considered to be similar to "wear and tear." The warranty booklet for the 2018 Volt battery says the battery may lose "up to 40%" of the original capacity in 8 years/100K miles and still be within warranty specs. The 2019 warranty booklet for a Subaru PHEV says, "the battery will experience natural and gradual capacity loss over time... This gradual capacity loss is not covered by any Subaru warranty."

One internet source mentions: "Federal law requires automakers to warranty EV and hybrid batteries for at least eight years or 100,000 miles. California requires a 10-year, 150,000-mile warranty on EV and hybrid batteries. Still, EV battery warranties vary considerably, especially when it comes to degradation." In general, the required coverage is for all components inside the high-voltage battery, but not necessarily for simple loss of capacity.

Not sure if the text of any extended warranty would even address the issue of loss of capacity. I note the sample contract for the Ally Major Guard coverage specifically excludes electric/hybrid vehicle battery packs. The same sample contract does say that if you have selected Major Guard EV, the exclusion for electric/hybrid vehicle battery packs does not apply. However, I cannot locate any description of such coverage, other than it covers the "Propulsion battery pack." Can anyone provide any specific terms for this extended battery coverage (i.e., anything more than "covered against any defects in materials and workmanship ")?

Thus this extended warranty for the Volt’s battery may not cover any loss of capacity over time, but might only cover "failure of the parts within the battery." Keep in mind the propulsion system for the Gen 2 Volt is designed to blend two propulsion torque sources to achieve full performance, using the larger motor plus the gas engine when extending the range. The Gen 2 Volt can blend in propulsion torque from the gas engine under high torque acceleration conditions, limiting the need to pull high levels of acceleration power from the battery when driving with a fully depleted battery. It is possible the Gen 2 Volt may lose a significant amount of ev range per full charge before any component inside the battery "fails."

I just called Ally and spoke with a lady in the claims department and she said the traction battery is covered to the extent the factory warranty covers it for degradation for the duration of the contract. My wife has the car now so I don't have access to the owner's manual at the moment. This is from the online Voltec warranty info.

"Like all batteries, the amount of energy that the high-voltage “propulsion” battery can store will decrease with time and miles driven. Depending on use, the battery may degrade as little as 10 percent to as much as 30 percent of capacity over the warranty period. A dealer service technician will determine if the battery energy capacity (kWh storage) is within the proper limit, given the age and mileage of the vehicle. Your Volt battery warranty replacement may not return your vehicle to “as-new” condition, but it will make your Volt fully operational appropriate to its age and mileage."
I'm going to the dealership tomorrow to try to nail it down firmly, like in writing.

They do not have a period that the vehicle has to wait time and/or distance before it is fully covered.

If the lady in the Ally claims department said "the traction battery is covered to the extent the factory warranty covers it for degradation for the duration of the contract," I interpret that to mean the Ally extended contract contains no text mentioning battery degradation coverage. The only "degradation" warranty coverage is that provided by the language in the factory warranty, i.e., any degradation coverage would expire at the 8 year / 100K mile mark.

The Support section of the mychevrolet.com website can provide you with the owner manuals and warranty manuals in pdf format for most of the Volt model years (for some reason, the 2013 warranty manual is not listed), including Chevrolet’s "2018 Limited Warranty and Owner Assistance Information" manual.

Note that the "new vehicle limited warranty" for the Gen 1 and Gen 2 Volts includes two emissions-related warranties covering defects in materials and workmanship, one for emissions-control parts for 8 years / 80K miles, and one for Voltec-related parts, including the high voltage battery, for 8 years / 100K miles.

The Chevrolet battery warranty section contains language addressing degradation. For Gen 1 Volts, the battery may lose "up to 30%" of the original capacity in 8 years/100K miles and still be within warranty specs. For Gen 2 Volts, that has been revised to read "up to 40%" of the original capacity in 8 years/100K miles and still be within warranty specs. Wikipedia tells us the Gen 1 Volts were programmed to use 65% of the full battery capacity for Electric Mode driving. For the Gen 2 Volts, that window has been expanded to 76% (18.4 kWh full capacity, 14 kWh usable). That expanded portion of the battery used for electric mode driving has increased the potential for capacity loss over time, leading to the increase in the amount of capacity loss that may occur in the Gen 2 and Bolt batteries and still be within warranty specs.

And if "degradation" is not specifically covered in the Ally contract, then if your primary interest in obtaining this extended warranty is specifically for any coverage it may provide for your Volt’s high voltage battery, then perhaps the question to be asked is: "To what extent may the Gen 2 Volt battery be subject to failure after eight years of use for reasons other than simple loss of capacity over time?" IOW, do BEVs seem to suffer battery failures at the same level they seem to happen to Gen 1 Volts, or is there something unique to the stresses placed on the Gen 1 Volt battery when the range is being extended?

As I wrote earlier, driving a Gen 2 Volt with the battery fully depleted is far less stressful on the battery than driving a Gen 1 Volt with the battery fully depleted because the Gen 2 Volt has been reengineered to use the gas engine as a primary source of propulsion torque when needed when extending the range. This reduction in the amount of high power level demands made on the battery as a power source when the charge in the battery is approaching the bottom of the cell voltage discharge curve, I suggest, will contribute to preserving the health of the Gen 2 Volt battery over time. Perhaps others following this discussion have other thoughts on potential sources of Gen 2 Volt battery "failure" other than simple loss of capacity beyond the period of the factory warranty.