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Range anxiety is a considerable concern with electric cars, though for many people only for a subset of their journeys. A particular aspect of this is the difficulty and expense if you do run out.

In the olden days in situations where we might be short of range in an ICE we might put a petrol can in the car, though we would consider keeping it empty unless in extremis for safety.

You can get "Portable Power Stations", which I assume are big batteries not a millions miles away from both ones phone and EV battery. At least one is advertised on youtube as being suitable for charging electric cars. It has 3600Wh (and 4500W [sic] with an extra battery) and weighs 45kg. Its car power output is quoted as 12.6V, 10A, 126W Max.

Would it be plausible to usefully put such a product in the trunk as an emergency source of charge on occasions when one may be at risk of running out? I can imagine it being used both as a "one off" charge and an item one could charge somewhere where one could not charge a car. I would imagine it only making sense if one was much more price conscious than time conscious, and have another financial justification for the power pack.

User65535
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If you consider the size of the existing battery in an EV that can provide from 100 miles to 400 miles and segment it to a fraction of the pack, you can see that any useful additional range is going to be too small if the segment will fit in a trunk.

Our EVSE charges our EVs at a rate of about 30 miles per hour and provides approximately 10kW to accomplish this. The equivalent in a portable unit is going to be rather large. One may make a compromise in speed, accepting a minimum 3 miles per hour, but that's still going to require the same amount of power, available only from the mass of battery to provide that energy.

Your referenced Portable Power Station at 45 kg (99 pounds) would be extreme and provide so little reserve. Both of our EVs have the ability to charge from a 120V source, although your reference is 12V, which further reduces the value of such a device.

I have seen reference in the EV forums of vehicles to be used for rescue purposes for EV drivers who are unable to manage the energy available. They are typically short flat-bed rigs with high power generators and level 2 and level 3 EVSE units. If the rescued vehicle is not capable of level 3 (DCFC), a long wait is to be expected and I suspect the rescue expense would be commensurately increased.

An aspect not to be overlooked is that range anxiety is popular in the negative-EV media. My experience over the past 17 years is that one need only be able to read the dashboard information and plan one's trip carefully. Of course, with petrol stations populating the map in a manner akin to fast food locations, it's easier to be lax with an ICE than an EV.

The 'net contains a few examples of people who have created range extenders, mostly comprised of a trailer and a conventional, but high output generator. This is a more portable version of the rescue vehicle described above.

Other examples are salvaged battery packs from another EV, charged independently and wired in a sometimes risky manner to the main vehicle. More weight, more drag, more complexity, more risk/danger, but yes, more range.

fred_dot_u
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In concept, additonal batteries could be used to extend the range as you suggest, but the device you are referencing is nowhere near powerful enough to provide any useful additional range. EVs run on much higher voltage systems and have drastically higher capacity. Any battery device that would be useful to extend range would not be portable, it would fill the entire trunk. Bear in mind that most EVs fill almost the entire bottom of the car with just batteries to provide their normal range.

cscracker
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