What is the difference between lithium battery and nickel cadmium battery?

There are seven main differences:

1, different materials: lithium battery with carbon material (graphite) as the negative pole, with lithium compounds as the positive pole; The positive electrode is composed of nickel oxide powder and graphite powder, and the negative electrode is composed of cadmium oxide powder and iron oxide powder.

2. Different working principles: lithium battery is more equivalent to a charge container, which basically does not rely on electrochemical reactions. When charging the battery, lithium ions are generated on the positive electrode of the battery, and the lithium ions generated move to the negative electrode through the electrolyte. As a negative carbon, it has a lamellar structure, and it has many micro pores. Lithium ions that reach the negative electrode are embedded into the micro pores of the carbon layer. The more lithium ions embedded, the higher the charging capacity. Similarly, when the battery is discharged (the process by which we use the battery), lithium ions embedded in the negative carbon layer escape and move back to the positive electrode. The more positively charged lithium ions, the higher the discharge capacity. Nickel-cadmium batteries require electrochemical reactions. During charging, electrons travel along the wires to the cathode, and nickel dioxide at the cathode reacts with water in sodium hydroxide solution to form nickel hydroxide and hydroxide ions. Electrical energy is converted into chemical energy. Cadmium (Cd) and hydroxide ions (OH-) in NaOH at the negative electrode combine to form cadmium hydroxide, which is attached to the anode.

3, charging and discharging characteristics are different: lithium battery on the charge and discharge current has strict control, can not be too large, and the discharge voltage gradually decreased, the change is large, but lithium battery charging efficiency is high, and no memory effect; Nickel-cadmium battery can charge quickly with large current, and provide large current for the load, and the voltage change is very small when discharging, but its charging efficiency is low, the memory effect is serious;

4. Different single-section voltages: 3.6v or 3.7v for lithium batteries and 1.2v for nickel-cadmium batteries;

5, durability characteristics are different: lithium batteries are more fragile, over discharge or over charge will cause permanent damage, so the need to install protection circuit board, and about half a year between the need to charge and discharge maintenance; Nickel-cadmium battery can withstand overcharge or over discharge, simple and convenient operation, long-term placement will not make the performance degradation, when the charge can be restored to the original characteristics;

6. Different charge volume ratio: lithium battery has a higher charge volume, and the same weight and volume can store more charge than nickel-cadmium battery;

7. Different environmental features: nickel cadmium batteries are toxic to cadmium, so nickel cadmium batteries are not conducive to the protection of the ecological environment. Due to many shortcomings, nickel cadmium batteries have been basically eliminated from the application range of digital equipment batteries. Lithium batteries, which contain few toxic elements and have little impact on the environment, are widely used in digital electronic devices.

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