Would it even actually charge though?
I mean most vehicles have some draw on the battery even when they're "off". Stereos, a clock, alarm systems, remote start systems, GPS, etc... So I guess the more important question is would the USB port even be able to supply enough power to counter those draws? If not then it wouldn't matter how long you plugged the vehicle in via usb for because it simply would never charge.
If you're having money problems and need to charge a battery somehow it'd probably better for you to carry a portable booster pack so you can give some actual charge when necessary.
Though if you're having money problems, going with an electric vehicle is likely not the best answer. They tend to be way more expensive than a traditional car. (The cheapest electric cars tend to start at $30,000. You can get a brand new gas car, like a Kia or Hyundai, for half that. Once you get into the 30,000 range you might as well look at Volkswagen or Honda then which give usually very good fuel mileage and are known for quality... )
Even buying used you're unlike to find many electric cars (since they're kinda new and not many around yet). So it's pretty much going to be a gas car... Which you can get a decent one for under $3,000.
Additionally repairs on electric vehicles tend to be extremely expensive. I mean buying a battery for a regular car is within the $130 range. Electric cars can use between 4 and 8 of them (if they use standard car batteries). So when the batteries in them start to go it's a very expensive fix. Plus, like for the smart car, they're often proprietary batteries too so you can't even go to a standard car shop and buy any old battery. (Smart cars use a lithium-ion battery more akin to a smartphone.)
Also, is it actually cheaper to run an electric car? Let's say the average fuel economy for cars is 30mpg with a 10 gallon tank... So your range is roughly 300 miles (500 kilometers for non-Americans) on full. Average price of fuel in the USA is ~2.54 at the moment. So roughly $25.4 to fill a normal car.
For electric cars the price depends on when/where you recharge. At home during peak usage? Maybe as much as 47 cents per kilowatt hour. Which means to get a full charge means you could pay anywhere from 2.82 to 5.64 to go approx 63 miles.
To put that in comparison...
To go 300 miles in a smart car you'd be looking at prices of 13.42 to 26.84... And 4.7 stops to recharge (for up to 12 hours per charge).
Or if you charge at home during off peak hours it could be much lower... But you'd have to pay way more attention to the charging rates/times to get the best value. And that'd mean a lot more careful planning.
Most Electric cars still have a smaller box sized 12 Volt regular car battery for running accessories like the clock, stereo, radio, gps, and other electronics according to
https://www.quora.com/Why-do-Tesla-cars-have-a-12-volt-starter-battery
"The car industry is de facto standardised on 12v electrical systems. The lights, horn, radio, and just about everything else runs on 12 volts, as do all the accessories that you can plug in. So the Tesla needs a 12v system."
-Peter Murias, Automotive engineer, maintain my own vehicles
Answered Apr 12, 2016
The 12V battery can go dead if you don't drive your car for a long time, so you need to jump start it, and plugging in your electric car charger may not work at charging the 12V battery if the car charger was not designed to charge both batteries.
Carrying a battery booster pack design for electric cars will be the best thing to do if you have money problems. But, drivers don't always prepare themselves for running out of electricity. Using laptop USB-C charger may very slowly charge up a car battery where it is charge a few extra percentages like 5% to drive a short distance to the closest building with a faster electric car charger.
Most people with money problems will pick a gas car since there are a lot of reliable used gas cars which people can buy for a few thousand dollars, and some new cars like the Nissan Versa which is sometimes on sale for $10000 or less for the manual transmission version.
Some people with money problems may pick an electric car because of the high price of gas because of expensive local gas taxes and they think gas prices will become more expensive because of a war, low gas supply crisis, or greedy oil companies which may raise the price of gas in the future to earn more money. There are also some tax savings when buying a electric car if your government gives tax discounts to electric car buyers.
There are a few more affordable electric like the Renault Twizy which cost $17,000 Canadian dollars/$13,800 USD according to
Renault Twizy To Be Sold In Canada From $17,000 It has 2 seats, and an automatic transmission. But, the cheapest model of the Twizy has a top speed of 40 km/h/25 mph, so it is not designed with a high speed limit, so a faster similarly priced gas car like a Hyundai Accent sedan would be a better choice.
When electric car becomes more popular, the price of batteries and electric car parts may become cheaper as more third-party car parts makers make parts for electric cars.
The price of gas and electricity can become more expensive and cheaper depending on how much energy companies decide to sell their gas or electricity for. I think one of the advantages of electricity is you can generate your own electricity with solar panels, a wind turbine, etc and use the electricity you generated to help power your house, and sell un-used electricity back to the power company if you are generating too much electricity which you are not using.
