First and second hearing assistance devices each comprise a rechargeable power source and power management circuitry configured to control charging of the power sources. A portable charging unit comprises an interface configured to receive a connector of a power cable or a power and data cable, a rechargeable power source coupled to the interface, first and second charge ports configured to receive the first and second hearing assistance devices, and charging circuitry coupled to the first and second charge ports and to the rechargeable power source of the charging unit. The power management circuitry and the charging circuitry cooperate to partially charge the power sources of the hearing assistance devices at an accelerated charge rate above 1.0C when a state of charge (SoC) of the power sources is within a predetermined SoC range.