The capacity of Alkaline battery is higher than that of carbon battery. The reason is that the manganese dioxide used as the cathode has higher purity and density. It is 3 to 5 times more capacity than carbon batteries. However, the capacity of the Alkaline battery will decrease with the increase in output current. For example, the same battery can have a capacity of 3000mAh at low output current, but when used in a load with 1A current, the capacity will only be 700mAh, which is less than 1/4 of the original.

The electromotive force (e.m.f) of a single Alkaline battery, that is, the voltage at no load is generally 1.5V, but the voltage varies between 1.5V and 1.65V with different manganese dioxide and zinc oxide. When the load is connected, the newly added voltage with the output current will drop, and the voltage will drop to between 1.1V and 1.3V under normal load.



Alkaline battery can output more current than carbon-zinc battery, but smaller than ordinary battery. Alkaline batteries with larger capacity can output larger currents because of the increased electrode area and more substances that can react chemically at the same time. Excessive current will heat up the battery during the discharge process. Generally, AA batteries can output 700mA current without heating up significantly, while larger models of C and D batteries can withstand greater current without heating up significantly.

The essential difference between carbon batteries and Alkaline batteries lies in their internal materials. In addition, the structure of Alkaline batteries is completely opposite to that of acid batteries. The center of the battery is the negative electrode, the zinc is in powder form, and the positive electrode area is in the outer layer. It is a mixture of MnO2 and KOH. It's a steel cylinder. Alkaline battery overcomes the shortcomings of acid battery storage time and unstable voltage, but it is still a disposable battery.

Alkaline battery is 3-7 times the capacity of carbon batteries, and the price is 1.5-2 times that of carbon batteries. Carbon batteries are suitable for low-current electrical appliances, such as clocks, remote controls, radios, etc., Alkaline batteries are suitable for high-current electrical appliances, such as BP players, CD players, electric toothbrushes, electric toys, handheld computers, etc.. Unlike carbon batteries, the chemical composition and structure of alkaline batteries are different, but the output voltage is the same.