Heating the battery to its optimum charging temperature, just before charging should produce a faster charging rate from the "Get Go" and therefore resulting in quicker charge cycle time. Something worth considering though, if you are running low on range then preheating the HV battery WILL reduce your remaining range even further !.
What is battery preheating?
The ultimate goal of battery preheating is to recover battery performance as quickly as possible at low temperatures while considering battery friendliness, temperature difference, cost, safety and reliability. A systematical review of low temperature preheating techniques for lithium-ion batteries is presented in this paper.
In summary, an efficient and evenly preheating of the battery at low temperatures can be achieved by selecting the appropriate AC parameters. However, the impact of quantified AC on battery health remains unclear.
Does preheating improve battery performance under cold weather conditions?
The features and the performance of each preheating method are reviewed. The imposing challenges and gaps between research and application are identified. Preheating batteries in electric vehicles under cold weather conditions is one of the key measures to improve the performance and lifetime of lithium-ion batteries.
Due to low thermal conductivity and high space requirement, air preheating is only suitable for early generation EVs with low energy density batteries. At the moment, liquid preheating is the most commonly used method since it has demonstrated good preheating performance and consistent temperature distribution.
The first category is self-heating technology, which uses the battery's energy to preheat the battery. The second category is current excitation technology, which usually requires an applied current excitation and generates heat through the internal impedance and thus preheats the battery.
Battery performance and potential risks under low temperature. Preheating techniques are key means to effectively mitigate battery performance degradation at low temperatures and stop safety problems from occurring . During preheating, there are two modes of heat transfer path, convection and conduction.