3.7V Lithium Polymer Battery

　　Nickel-metal hydride battery technology training: the principle of nickel-metal hydride batteries

　　Nickel-metal hydride battery technology training provided by electronics enthusiasts: the principle of nickel-metal hydride batteries material, also known as hydrogen storage alloy (electrode is called hydrogen storage electrode)

　　Nickel-metal hydride battery technology training: the principle of nickel-metal hydride batteries

　　The positive active material of the Ni-MH battery is nickel hydroxide (called nickel oxide electrode), the negative active material is metal oxide, also known as hydrogen storage alloy (the electrode is called hydrogen storage electrode), and the electrolyte is 6N potassium hydroxide. The cell reaction during the process is:

　　Wherein, M represents the hydrogen storage alloy material. The open circuit voltage of the battery is: 1.2V ~ 1.3V, which varies with different hydrogen storage materials and preparation processes. When overcharged, the reaction on the two poles is: on the nickel oxide electrode: 4OH`-4e—2H2O+O2

　　On the hydrogen storage electrode; 2H2O+O2+4e—4OH`

　　Overall reaction when the battery is overcharged: O

　　In the design of the battery, the method of using an excess of the negative electrode is generally adopted. When the nickel oxide electrode is fully charged, oxygen is generated and recombined into water at the negative electrode after diffusion. A giant change has taken place. When the battery is over-discharged, the electrode reaction is:

　　On the nickel oxide electrode: 2H2O+2e—H2+2OH`

　　On the hydrogen storage electrode; H2+2OH`-2e—2H2O

　　Overall reaction when the battery is over-discharged: O

　　Although the net result of the total reaction of the battery is zero during over-discharge, the phenomenon of reverse polarity will occur. Since the hydrogen generated on the positive electrode will be newly combined on the negative electrode, the stability of the system is also maintained. In addition, hydrogen, the active material of the negative electrode, can be absorbed in the dry hydrogen storage alloy at a relatively high density in the hydrogen atomic state. On such an electrode, the hydrogen absorption and desorption reaction can proceed smoothly, and the discharge performance is improved compared with the cadmium-nickel battery.