An analyte sensor system is provided. The system includes a base configured to attach to a skin of a host. The base includes an analyte sensor configured to generate a sensor signal indicative of an analyte concentration level of the host, a battery, and a first plurality of contacts. The system includes a sensor electronics module configured to releasably couple to the base. The sensor electronics module includes a second plurality of contacts, each configured to make electrical contact with a respective one of the first plurality of contacts, and a wireless transceiver configured to transmit a wireless signal based at least in part on the sensor signal. The system includes a first sealing member configured to provide a seal around the first and second plurality of contacts within a first cavity. Related analyte sensor systems, analyte sensor base assemblies and methods are also provided.