Whenever the temperature changes, we make adjustments. It’s cold? Layer up. It’s hot? Layer down (but not too much). It’s temperate. Haha. Since when? But the same idea applies to EVs. Drive routes and trip planning need to be adjusted because range and charging times will fluctuate with the thermometer. However, for the summer months, there may be a hack for that.
Called the wet-towel trick, it’s as basic as it sounds. If a charging station handle is too hot, throw a damp cloth over it to cool it down and increase charging speeds. Easy, but does it actually work? According to InsideEVs, yes, it does. At least at Tesla Supercharger stations.
Those charging stations monitor cable temperatures, among other things, for safety and longevity. But apparently, the sun beating down on said cables can prematurely cut charging speed, particularly at older charging stations. To cool them back off, people are, well, covering them with towels.
Being outside for an extended period isn’t ideal when the heat index rises. And if you’re (un)lucky, you get a nice facepunch of humidity to add to your strife. Yet, something as simple as a cold, wet towel offers instant relief. I grew up in the tropics, so I get it, as would anyone who exercises, works, or hobbies outdoors.
This same idea applies to the hot handles. Anyone who’s charged an EV, even if just once, knows that the as-advertised charging speed posted at the station is pretty much what you never get. Not only can the number of vehicles connected throttle charging speeds, but so can the ambient temperature.
Also, older V2 Supercharger stations feature charging cables that don’t have a cooling mechanism. In this case, sun exposure can heat up the handles enough to trigger a sensor to slow the charge to keep within safe operating temperatures. But a handy-dandy hydrated wrap just might cool the handle enough to speed up the charging rate.
InsideEVs laid out a couple of wet-rag examples. In one, a V2 Supercharger went from 60 kW to 95 kW. Another Tesla owner experienced a jump to 119 kW from 58 kW. Obviously, YMMV, but as Ford CEO Jim Farley can attest, we’ll take all the kW we can get whenever we can get them. It’s worth noting that the towel trick doesn’t appear to work at V3 Superchargers, unless you’re charging a Cybertruck (i.e., bigger battery plus bigger power draw equal bigger charger temps).
OK, you’re thinking this is silly TikTok science. All viral and no sense because water and electricity don’t mix. Duh! EV chargers—Tesla or otherwise—are manufactured to be safely used in the rain. So theoretically moisture on the charge cable handle shouldn’t create any issues, though there might be unintended consequences of externally reducing the charge cable’s temperature.
The vehicles themselves have safety monitors as well to slow or stop charging. A soggy shirt or whatever you use should be of little consequence. Not that anyone is saying this is sanctioned. As with any internet find, use at your own risk.