A comprehensive comparison of chemical batteries

1. Lead-acid battery: reaction principle of lead-acid battery, that is, when charging, Pb2+ near the positive electrode loses two electrons and reacts with H2O to generate PbO2, and (HSO4)-; ​pb2 + gains two electrons near the negative electrode to form Pb, and the cell interior (HSO4)- migrates to the negative plate. When it discharges, the positive electrode PbO2 gains two electrons and generates

Pb2+ and H2O, spongy Pb on the negative lead plate loses electrons to form Pb2+. During the whole electrochemical process, the solution concentration changes with the decomposition and generation of H2O. The voltage of the lead-acid battery is around 2V, and the reaction electron migration number is 2.

2 lead carbon battery: lead carbon battery reaction principle is the same as the lead acid battery reaction principle.

A comprehensive comparison of chemical batteries

3. Lithium ion battery: relies on the migration of lithium ion to complete the storage of energy in the release, charging the positive lithium ion embedded in the negative carbon material, discharge lithium ion from the negative out, so lithium battery is also known as "rocking chair battery". The potential of lithium ion is very high, and the voltage is slightly different for different cathode materials. The voltage of ternary battery is 3.7V, the voltage of lithium iron battery is 3.2V, and the voltage of lithium titanate battery is about 2.5V.

4. Vanadium battery: In the reaction process of vanadium battery, the positive electrode V2+/V3+ pair has the electrode potential of -0.25V, and the positive electrode V4+/V5+ pair has the electrode potential of 1.0V. The total potential of vanadium battery is 1.25V. Affected by the change of ion concentration, the charging voltage in actual operation is 1.25-1.6V. The discharge voltage is about 1.25-1V. The electron transfer number is one.

5. Zinc-bromine battery: zinc-bromine battery reaction process has no side reaction. The negative electrode Zn/Zn2+ pair of Zinc-bromine battery has an electrode potential of -0.76V, while the positive electrode Br/Br- pair has an electrode potential of 1.087V. The total potential of Zinc-bromine battery is 1.85V. The actual charging voltage of Zinc-bromine battery is 1.95V, which is little affected by the change of ion concentration during actual operation. The average discharge voltage is about 1.65V. The electron transfer number is 2.

6 sodium sulfur battery: battery is metal sodium (Na) and elemental sulfur (S) and carbon (C) complex used as active substances in the anode and cathode, beta-alumina (beta-al2o3) ceramic plays the dual role of diaphragm and electrolyte. The equation of sodium-sulfur cell is 2Na+xS=Na2Sx. In the initial stage of discharge (sulfur content is 100%-78%), the positive electrode is composed of liquid sulfur and liquid NA2S5.2 to form a non-common solution phase, and the electromotive force of the battery is about 2.076V. When Na2S3 appears, the electromotive force of the battery drops to 1.78V. When the discharge occurs to NA2S2.7, the corresponding electromotive force drops to 1.74V until the liquid phase disappears.

7 hydrogen fuel cell: hydrogen through the pipeline or gas guide plate to the anode, under the action of the anode catalyst, 1 hydrogen molecule dissociated into 2 hydrogen protons, and releases 2 electrons, the anode reaction is: H2→2H++ 2E. At the other end of the cell, oxygen (or air) reaches the cathode through the pipe or the air guide plate. Under the action of the cathode catalyst, oxygen molecules and hydrogen ions react with electrons arriving at the cathode through the external circuit to form water. The cathode reaction is: 1/2O2+2H++ 2E →H2O. Electrons form direct current in the external circuit. Thus, as long as hydrogen and oxygen are continuously supplied to the anode and cathode of the fuel cell, electrical energy can be continuously exported to the load of the external circuit.

8. Zinc air battery: battery to "zinc" as fuel, after discharge into "zinc oxide", through electrolytic reduction, and then back to "zinc", more than the cycle, "zinc" no loss, just as the carrier of electric energy. Zn + 2OH -2e → ZnO + H2O (negative electrode); 1/2O2 plus H2O plus 2e goes to 2OH minus.

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