Ageing （老化）- Permanent loss of capacity with frequent use or
the passage of time due to unwanted irreversible chemical reactions in the cell.
Anode（阳极） - The electrode in an electrochemical cell where oxidation takes place, releasing electrons.
During discharge the negative electrode of the cell is the anode.
During charge the situation reverses and the positive electrode of the cell is the anode.
Cathode（阴极） - The electrode in an electrochemical cell where reduction takes place, gaining electrons.
During discharge the positive electrode of the cell is the cathode. During charge the situation reverses and
the negative electrode of the cell is the cathode.
Cycle （循环）- A single charge and discharge of a battery.
Depth of discharge DOD （放电深度）- The ratio of the quantity of electricity or charge removed from a cell on discharge to its rated capacity.
Internal impedance（交流内阻） - Resistance to the flow of AC current within a cell. It takes into account the capacitive effect of the plates forming the electrodes.
Internal resistance （直流内阻）- Resistance to the flow of DC electric current within a cell,
causing a voltage drop across the cell in closed circuit proportional to the current drain from the cell.
A low internal impedance is usually required for a high rate cell.