Does Cold Weather Affect Lithium Battery Life
Cold weather does affect battery life, even with lithium batteries. Temperatures below the 32 degrees mark will reduce both efficiency and usable capacity of lead-acid noticeably, providing 70-80% of its rated capacity. at the same temperature lithium batteries can operate with very little loss providing 95-98% of their capacity.
When charging at above-freezing temperatures, the lithium ions inside the battery are soaked up as in a sponge by the porous graphite that makes up the anode, the negative terminal of the battery. Below freezing, however, the lithium ions aren’t efficiently captured by the anode. Instead, many lithium ions coat the surface of the anode, a process called lithium plating, which means there’s less lithium available to cause the flow of electricity and the battery’s capacity drops. Charging below freezing at an inappropriate charge rate, also causes the battery to become less mechanically stable and more prone to sudden failure.
In freezing charging conditions, lithium ions get lost navigating their way to “work” within the graphite anode. Instead of intercalating, these ions end up plating the surface of the anode. Charging in freezing temps can cause plating, which reduces battery capacity and increases resistance. If enough plating builds up, it can puncture the separator and create a dangerous short inside the cell.