The best car battery always decides from its cranking power.The best car battery decides its manufacturers used raw material its totally materila based technology here dont haver any rocket science.

Current is not a fundamental component of electricity. The fundamental component is charge. Batteries store two species of chemicals, one that can undergo an oxidation reaction releasing electrons when those electrons can flow away from the anode, and one that can undergo a reduction reaction that absorbs electrons from the cathode when electrons can flow into the terminal.

The battery is constructed so the flow of electrons between anode and cathode is inhibited. This inhibits the internal reactions due to the electric fields between the electrodes. Connecting an external circuit to the battery permits the charge to move creating an external current flow between the terminals.

This flow will be modulated by changes in the impedance of the connected circuit. It will, therefore, have both AC and DC components. For a primary battery, the minimum magnitude for the current is required to be zero, since providing a potential across the battery larger than the open-circuit potential of the battery can damage it.

For rechargeable batteries, an external potential greater than the open-circuit potential of the battery can reverse the chemical reactions at the electrodes, reduction at the anode and oxidation at the cathode to recharge the batteries.

For these batteries the AC component of the charge flow can drive the magnitude to a net negative within the limits reverse chemical reactions to absorb and/or release the electrons without damage to the battery.

In summary, the problem with this question is treating current as an entity that possesses the property of “AC”, or “DC”. Current is, rather the measurement of the flow of the fundamental element of charge, which can have “AC” or “DC” components.

It is the forces applied to the charge that creates current. There is no such thing as an “AC” charge or a “DC” charge.