Gizmos & Gadgets: On Cold Days Does Your Smartphone Lose Its Charge? Soon That May End

March 5, 2018 – Lithium-ion batteries don’t like the cold. That’s why electric vehicles (EVs) operating in cold countries get reduced mileage per charge. The same is true for your smartphone. When temperatures drop below 0 Celsius (32 Fahrenheit) degrees the electrolytes in the batteries lose viscosity and eventually as temperatures drop further can freeze. That means less conductivity and a battery that drains faster than you can place a call to tell your spouse you’re freezing when walking your dog.

I’ve noticed it particularly this year when I walk my pup, Maya (she’s not really a pup being 12 years old). I go out with a fully charged phone in my back pocket and come back 45 minutes later having made no phone calls, or checked emails, texts or Google, and yet the battery shows as much as a 25% drop.

But that battery problem may soon pass as scientists search for alternative electrolytes that can stand the cold. Two researchers at Fudan University, Shanghai, have experimented with organic-based chemical electrolytes that are showing considerable promise in retaining ionic conductivity in temperatures as low as -70 Celsius (-94 Fahrenheit). The electrolyte uses an ethyl acetate base and exhibits a capacity to retain a charge at 70% in -70 Celsius temperatures. At -40 Celsius (-40 Fahrenheit) the battery retained 83% capacity. And at 25 Celsius (77 Fahrenheit) 100% retention. The researchers are still playing around with the material composition of the anodes and cathodes to go along with their new organic electrolytes. The material for the cathode is made of polytriphenylamine. The anode is composed of naphthalene tetracarboxylic dianhydride. Talk about two real tongue twisters.

From the laboratory to commercial reality is the next big step. But don’t be surprised if the next generations of smartphones and EVs operate much better when a polar vortex descends on your locale in a future winter.