Low powered variable voltage E-Cigarette batteries under perform at higher power settings.

Electronic Cigarettes (EC) use continues to increase with many efforts underway to develop dose-response relationships for clinical and sub-clinical purposes. This study investigated the battery performance of several variable voltage (VV) ECs capable of varied voltage outputs. Six brands of VV EC batteries were tested for dial setting accuracy (voltage) and power supplied during simulated vaping. All measurements were conducted using a single atomizer with two different resistance coils at four voltage settings in a blocked randomized structure. Battery dial settings were accurate when disconnected from an atomizer. When powering an atomizer during simulated vaping, all batteries supplied power linearly up to approximately 8.5 watts. Beyond 8.5 watts all batteries began to undersupply power, plateauing around 9-10 watts, depending on the specific battery. This behavior was not consistent with battery internal resistance. Undersupply of power at higher device settings will result in lower-than-expected nicotine (or THC) delivery and potentially lower pyrolysis products such as aldehydes. Studies seeking to associate VV EC power with psychological, physiological or toxicological effects should measure the actual power supplied or else a negative bias is likely to be observed in trials above 8.5 watts.