I'd be lying if I said I wasn't concerned about battery degradation over time, and due to freezing temperatures. But I am seeing no degradation at all in EV range after owning the car for 16 months, and having gone through 2 winters parked outside. I had expected to have lost a few percent over this time, and what I have read about low temperatures, is that a lithium-ion battery will be damaged from charging it in subzero temperatures. Parked outside, my Prius Prime was certainly exposed to subzero temperatures, sometimes as low as -30C. I can't attribute this to battery heaters, as I saw no additional power draw over the winter. My EV range did decrease in frigid temperatures, by as much as 50% in extreme cold, but I am seeing over 100% of the EV range I saw a year ago. Last year, the record EV range I saw was 61 kms, and this year, I have already seen 62 kms. Is this due to better battery chemistry, or better charging circuitry? The EV range indicated is well correlated to actual range as I have measured it.
Very much depends on the electrolyte and trace elements added in the lithium mix. Lithium Yttrium Ferrous Phosphate, or LYP chemistry, the charging temp can be as low as 30*C without an adverse effect. They build these cells to work in the satellites and the Mars Rovers, so they can build them to operate in some hostile environments. The balance is still the same when the operating temp is adjusted using the electrolyte, if the charging temp is lowered, the max operating temp is lowered by the same amount. When the chemistry is altered, the range expands, a lower and higher temperature range is achieved ..... Sodium ion is the new kid on the block and that has much better operating range, CATYL's new hybrid cell mix expands the capability even further, it will only get better ..... T1 Terry
