A technology described herein is for accurately determining the SOC of a secondary battery. Semiconductor dopant is introduced into the body material to define a more heavily doped pocket portion using the gate electrode as a dopant-blocking shield. A gap may be detected by comparing the times of events in the stream. The nose element may be an elastomer, and may be a cylindrical body. The two-part base has a second mating member, whereby the two-part base is connected to the container body adjacent the bottom of the container body via a mating connection between the first mating member and the second mating member.