I have tried something like that but it fried the inflator even though the inflator has an overvoltage circuit (supposedly will give an error code over 15v). The jumpstarter output is 15v / 10a but that shouldn't be too much different than a car lighter with engine running. I don't know if it was a fluke, but I would be careful trying anything like this especially if the output is greater than 12v

Here is the inflator I used but I am guessing the internal circuitry is similar for many differently branded items: https://www.amazon.com/gp/product/B07V1LCKX9

The jumpstarter has a cigarette lighter adapter that is rated at 15v 10a based on power label. Here is the jump starter: https://www.amazon.com/gp/product/B07QDXL1PW

I haven't yet put a voltmeter on it, but I think most lithium ion chargers would have a 14.8v battery due to 4 cells at 3.7v each. Given car alternators can output a similar voltage, I was surprised that the inflator fried, especially since it was supposed to protect against overvoltage, but it could have been a fluke.

Here are some more details: I used it a few times and it threw a high voltage error code (flashing U-H) but could be coaxed to work when the battery in the jump starter wasn't fully charged. However, when I fully charged the battery, it completely fried the inflator. It ran but it couldn't be turned off and then after that it would no longer work in normal 12v plugs.

Once I test the jumpstarter cigarette adapter output with a voltmeter, I will report if there was something wrong with the jumpstarter but given my outcome, I would be careful experimenting with jumpstarters as batteries if they output greater than 12v, especially if your pump isn't still covered under warranty.