It is widely known that battery life would drop while the temperature is decreasing.
We found some professional information based on the laboratory studies from "batteryuniversity.com", a shared forum about battery basics from Switzerland.
Figure: Capacity fade in storage and with a 25% cycle depth at different temperatures and SoC. (Source: Technische Universität München (TUM) Document: Aging of Lithium-Ion Batteries in Electric Vehicles)
The figure demonstrates capacity fading during cycling at low, medium and high state-of-charge (SoC) levels and at different temperatures. These readings are demonstrated in colored solid lines. The graph also illustrates calendar aging that is represented in dotted lines with less capacity loss that cycling. As we can see from the graph lines, the test battery had the highest capacity loss at 10°C (blue) with high SoC. High losses when cycling Li-ion batteries at cool temperatures. Li-ion should be warmed up to a comfortable temperature of about 77°F with operating temperature of up to 104°F.
And finally, our lovely Bikonit owners, please charge your e-bikes in a warm place (best around 77°F) to enhance your battery performance at low temperatures outside.
For more information about the battery life, please visit the site: Battery University.