Rechargeable electric drill nickel cadmium batteries and lithium battery which is good
Consisting of different materials: lithium battery with carbon materials (graphite) as anode, lithium containing compounds as anode; nickel cadmium battery cathode by nickel oxide powder and graphite powder as active material, anode active material by cadmium oxide powder and iron oxide powder.
Environmental characteristics are different: Cadmium in nickel cadmium batteries is toxic, and therefore, nickel cadmium batteries are not conducive to the protection of the ecological environment, many shortcomings make nickel cadmium batteries have been basically eliminated from the digital equipment, battery applications. The lithium battery basically contains no toxic elements, and has little impact on the environment, so it has been widely used in digital electronic equipment.
The charge discharge characteristics of different lithium battery: strict control for charging and discharging current, can not be too large, and when the discharge voltage is decreased gradually, but the change is bigger, the lithium battery charging efficiency is high, and there is no memory effect; nickel cadmium battery large current fast charging, and can provide high current load and discharge voltage change is very small charging, but its low efficiency, serious memory effect;
The working principle is different: the lithium battery is equal to a charge container, work basically do not rely on the electrochemical reaction, when charging the battery, lithium ion battery cathode is generated, the generation of lithium ion movement through the electrolyte to the cathode. As the anode carbon is layered structure, it has many micropores, and the negative ion is embedded into the micropores of the carbon layer. The more the embedded lithium ion, the higher the charging capacity. Similarly, when the battery is discharged (i.e., we use the battery), the lithium ions embedded in the negative carbon layer are removed and moved back to the positive electrode. The more lithium ion is back to the positive electrode, the higher the discharge capacity. Nickel cadmium battery work needs the electrochemical reaction, charging electronic along the wire to the cathode, and the cathode of the two water reaction of nickel oxide and nickel hydroxide and sodium hydroxide solution in the formation of hydroxyl ions, chemical energy into electrical energy; discharge cathode in cadmium (Cd) and sodium hydroxide (NaOH) in hydroxide ion (OH-) the synthesis of cadmium hydroxide, and attach to the anode, but also emit electron, chemical energy into electrical energy;
