2. Construction and the reaction of zinc-manganese batteries with salt electrolyte.

Construction of salt batteries. The salt body elements made of zinc, a negative electrode 1. The positive electrode 2 is a packet of compressed active mass, moist electrolyte, which is located in the center of the collector 3 - carbon rod impregnated with paraffin-based formulations to reduce water loss from the electrolyte. Top collector crimped metal cap. The electrolyte in the separator 4 - the thickened. The cells have a gas chamber 5, which receives the gases emitted during the discharge and self-discharge. Top place gasket 6. To reduce the likelihood of leaks due to pitting corrosion of the zinc thin-walled glass element is placed in a holder 7, cardboard or polymer, sometimes additionally used Case tinplate. In this case, the bottom and top of the element as close tinplate.

The electrodes and electrolyte. The active mass of the positive electrode (called "sinter") consists of a mixture of manganese dioxide flake graphite or acetylene black, and an electrolyte. Graphite and carbon black to increase the electrical conductivity of the active mixture. The higher discharge currents, which are calculated on the zinc-manganese element content of the above conductive additives. The negative electrode is made of a corrosion resistant high purity zinc (zinc mass fraction of 99.94% or more). The electrolyte in the cell system has previously been ammonium chloride solution. But later electrolyte solution of ammonium chloride was replaced by zinc chloride solution, sometimes supplemented with calcium chloride. The efficiency of such elements at reduced temperatures significantly higher than classical. To reduce the freezing point of the electrolyte composition is administered in its calcium chloride. When using ammonium chloride processes are described electrode current-producing reaction by the following equation: 2MnO2 + 2NH4Cl + Zn → ZnCl2· 2NH3 + H2O + Mn2O3. When using zinc chloride equation is: 8MnO2 + 4Zn + 2ZnCl2 + 9H2O → 8MnOOH + ZnCl2 · 4ZnO · 5H2O. Energy performance elements with zinc chloride electrolyte is much higher: at medium and high load currents, they can provide 1.5-2 times the duration of the work. The efficiency of at low temperatures is also higher.

Salt batteries. Until recently, the elements of this electrochemical system were most common in spite of the fact that they were among the first and remained virtually unchanged due to its characteristics: For manufacturer: - Cheapness and availability of raw materials;- Ease of production technology. For the buyer: - Lower final value determined by the low cost producer; - Ease of use; - Satisfactory for most applications, the electrical parameters. Among the disadvantages of salt batteries are: - A sharp voltage drop during discharge; - A significant reduction of given capacity with increasing discharge currents to the values necessary for modern devices; - A sharp deterioration in performance at low temperatures; - A small storage period (about two years).