Shares of electric car-maker and would-be Tesla (TSLA -1.11%) -killer Lucid Group (LCID 0.41%) gained a modest 3.5% through 11:50 a.m. ET on Monday.

The company is benefiting from some new PR that portrays its new Lucid Gravity electric SUV in a positive light relative to Tesla's Model S, X, and Cybertruck offerings.

Lucid's answer to range worry

Electric cars and trucks remain popular among certain car buyers, despite all the reports that they're not selling quite as well as hoped. One obstacle to greater adoption is that many car buyers still worry about running out of "gas" -- or more precisely, electricity -- because of these vehicles' limited range and inability to "fill up" quickly at a gas station.

Lucid's latest answer to this concern is the Lucid Gravity, a new luxury three-row electric SUV that it says will start below $80,000 MSRP -- and possess a driving range "in excess of 440 miles."

Compared to Tesla's flagship Model S sedan, the Tesla with the company's greatest driving range at 405 miles, that's at least a 9% advantage for Lucid. But then again, Lucid already had an advantage over Tesla sedans, with its Lucid Air Dream Edition R boasting a reported driving range of 520 miles. 

Compared to the Tesla Model X SUV with 348 miles of range, though, the Lucid Gravity boasts a 26% advantage versus Tesla's SUV. Compared to a Cybertruck (which, once in production, might conceivably offer a three-row configuration and cosplay as an SUV), the Gravity boasts a massive 65% advantage over Cybertruck's reported 267-mile range.

Is Lucid stock a buy?

These all sound like great reasons for car buyers to buy Lucid EVs instead of Tesla EVs. However, Lucid's problem is that no one seems to care. Car buyers are still choosing to buy Teslas rather than Lucids, and Lucid just earlier this month cut its production 2023 forecast from 10,000 units to somewhere between 8,000 and 8,500 units "to prudently align with deliveries."

Long story short, while driving range is important, it isn't the most important thing for Lucid stock. For stock investors, it's much more important that Lucid isn't selling enough EVs to earn a profit. Instead, Lucid is losing $2.6 billion a year, burning through $3.6 billion in cash a year, and only has $2 billion (net of debt) left on its balance sheet.

It's not how long a Lucid battery can last that should worry you. It's how long Lucid stock's cash will last.