Power-supply system, power-supply apparatus, and adapter

An adapter configured to be coupled between an electric work machine and a power-supply apparatus, the power-supply apparatus being configured to output a power-supply voltage to be delivered to the electric work machine, the adapter comprising:

• a power-supply attachment portion configured to detachably attach the power-supply apparatus thereto;
• a work machine attachment portion configured to detachably attach the electric work machine thereto;
• and
• an adapter communicator configured to perform, with the electric work machine, a digital communication in which a voltage level of an electrical signal is sequentially switched between a high level and a low level over time according to communication content, and to perform the digital communication with the power-supply apparatus.

A method comprising:

• coupling an adapter to (i) an electric work machine and (ii) to an power-supply apparatus, the power-supply apparatus being configured to output a power-supply voltage to be delivered the an electric work machine;
• performing a first digital communication between the adapter and the electric work machine;
• performing a second digital communication between the adapter and the power-supply apparatus;
• and
• delivering the power-supply voltage from the power-supply apparatus to the electric work machine through the adapter.