One common critique of battery-powered cars versus their gas-powered counterparts is that batteries degrade over time. In other words, their driving range capabilities diminish over time and with use. Internal-combustion engine vehicles don't suffer from the same problem.

But is this issue as bad as many might assume it is? According to Tesla's (TSLA 0.79%) just-released impact report, its vehicles' battery degradation is extremely minimal. In fact, it's arguably something consumers don't have to worry about. 

A Tesla Semi on a highway.

Image source: Tesla.

Battery-life extension is key

As part of Tesla's efforts to reduce its carbon footprint, management acknowledges that focusing on battery longevity is a superior path toward this goal, relative to battery recycling.

Yes, Tesla does work with third-party battery recyclers and even recycles batteries in-house. But management asserts it gets more bang for its buck environmentally and for its business by constantly looking for ways to extend the life of its batteries.

Tesla does everything it can to extend the useful life of each battery pack, including sending out over-the-air software updates to Tesla vehicles to improve battery efficiency when our engineers find new ways to do so. In addition, any battery that is no longer meeting a customer's needs can be serviced at a Tesla service center.

"Designed to outlast the vehicle"

But Tesla has arguably already made impressive progress in battery longevity. In its impact report, the automaker asserts that, on average, its vehicles lose only 10% of their range after 200,000 miles. A long-range Model 3, therefore, would see its range decrease from 353 miles per charge to about 318 miles.

A standard Model 3's 263-mile range would decline to about 237 miles. And in one final example of the company's longest-range vehicle, its highest-range Model S would still boast about 365 miles of driving range after 200,000 miles of use. 

Tesla's Model S, X, 3, and Y

Image source: Tesla.

As Tesla notes, vehicles in the U.S. are often scrapped after about 200,000 miles of driving. In Europe, Tesla estimates it's even lower -- at 150,000 miles. Considering Tesla's impressive range retention and the average mileage of scrapped cars, therefore, the company says its "battery packs are designed to outlast the vehicle."

Of course, Tesla wants even longer-range vehicles with improved efficiency. So you can expect the automaker to continue innovating in this space. But efficiency improvements from here will likely take time, as Tesla's electric cars already feature impressive initial range and range retention.

A million-mile battery?

For some time, Tesla has said it has a goal to build a million-mile battery -- particularly for high-mileage vehicles like taxis, delivery vans, and trucks. "A relatively small number of vehicles, such as taxis, delivery vans, trucks and buses account for a disproportionate amount of vehicle miles and, as a result, a disproportionate amount of emissions," Tesla said in its impact report. "A single future Tesla vehicle with a million-mile battery could be utilized over five-times more than an average vehicle in the U.S."

Achieving a million-mile battery would be an impressive feat. Fortunately, of course, Tesla could likely charge a higher price for high-mileage vehicles since they're usually used for business purposes.

So a million-mile battery may be more within reach than it might seem, as Tesla could simply make larger and more expensive batteries to pull this off. But the automaker will likely look for efficiency gains, as well, as it works toward this goal.