To put it plainly, charging is the transformation of electrical energy into chemical energy. When discharging, chemical energy is converted into electricity!
Lead accumulator
The most commonly used, the plate is made of lead alloy grid, electrolyte for dilute sulfuric acid. The bipolar plate is covered with lead sulfate. But after charging, the anode plate of lead sulfate into two lead oxide negative electrode lead sulfate into lead metal. When the discharge occurs, the opposite direction of the chemical reaction.
The electric potential of lead-acid battery is about 2 volts, batteries commonly used in series 6 or 12 volt battery discharge. When sulfuric acid concentration decreased, measuring electrolyte density method can be used to judge the battery charging or whether charging process can end.
The advantage of lead-acid battery is that the electromotive force is stable when it is discharged. The disadvantage is that it is smaller than the energy (unit weight, storage energy), and it is corrosive to the environment
The positive plate group, negative plate group, electrolyte and containers. The positive plate after charging is Tan two lead (PbO2), the negative plate is fluffy lead gray (Pb), when the two electrode placed in a concentration of 27% to 37% sulfuric acid (H2SO4) in aqueous solution, and lead sulfate the electrode reactions, two valence lead positive ions (Pb2+) transferred to the electrolyte, leaving two electrons in the negative plate (2e-). The positive and negative gravity around lead positive ions gathered in the negative plate and the positive plate, there is a small amount of lead in two water molecules under the effect of electrolyte (PbO2 the price of two) into the electrolyte, oxygen ions and water molecules combine to make two lead into an unstable substance, Pb hydroxide dissociable (OH4). By 4 the price of lead hydroxide ions (Pb4+) and 4 hydroxyl (OH) - 4:.4 The price of lead ions (Pb4+) in the positive plate, the positive plate is positively charged. Because of the negative plate is negatively charged, so the two plates have a certain potential difference, this is battery electromotive force. When connected to the external circuit, the current from the positive to the negative. In the process of discharge, electronic negative plate the external circuit by the constant flow positive plate, then in the internal electrolyte due to sulfate molecule ionization into hydrogen ions (H+) and sulfate anion (SO42-), in the role of the ion electrostatic field, two kinds of positive and negative ions respectively to move, reach the negative plate of sulfate anion and cation combined into lead sulfate lead (PbSO4). The positive plate, because the electronic circuit from the inflow, and the 4 is the price of lead ion (Pb4+) synthesis of 2 valence lead positive ions (Pb2+), and immediately with the sulfate anion binding near the positive plate of lead sulfate attached to the cathode.
With the discharge battery, positive and negative plate by sulfide, and sulfate in the electrolyte decreased gradually, and more water, which leads to the decline in the proportion of electrolyte in actual use, by measuring the proportion of electrolyte to determine the level of battery discharge. Under normal circumstances, lead battery should not be excessive discharge, otherwise it will make and active lead sulfate crystal material mixed together to form a small larger body, which not only increased plate resistance, but also in charge when it is difficult to restore, directly affect the storage pool capacity and life. Lead battery is the inverse process of discharge.
Lead the working voltage of battery smooth, using temperature and use current range, charging hundreds of circulation, good storage performance (especially suitable for dry charged storage), low cost, so it is used widely. The new lead alloy, can improve the performance of lead-acid battery. If use lead calcium alloy grid, can ensure the lead-acid battery floating current minimum, reduce add water and prolong its service life; the use of lead lithium alloy casting positive grid, it can reduce self discharge and meet the needs of sealing. In addition, the opening type lead-acid battery will gradually changed sealed and acid proof, explosion-proof and hydrogen type lead-acid battery.
蓄電池的放電,正負極板都受到硫化,同時電解液中的硫酸逐漸減少,而水分增多,從而導致電解液的比重下降在實際使用中,可以通過測定電解液的比重來確定蓄電池的放電程度.在正常使用情況下,鉛蓄電池不宜放電過度,否則將使和活性物質(zhì)混在一起的細小硫酸鉛晶體結成較大的體,這不僅增加了極板的電阻,而且在充電時很難使它再還原,直接影響蓄池的容量和壽命.鉛蓄電池充電是放電的逆過程.
鉛蓄電池的工作電壓平穩(wěn)、使用溫度及使用電流范圍寬、能充放電數(shù)百個循環(huán)、貯存性能好（尤其適于干式荷電貯存）、造價較低,因而應用廣泛.采用新型鉛合金,可改進鉛蓄電池的性能.如用鉛鈣合金作板柵,能保證鉛蓄電池最小的浮充電流、減少添水量和延長其使用壽命；采用鉛鋰合金鑄造正板柵,則可減少自放電和滿足密封的需要.此外,開口式鉛蓄電池要逐步改為密封式,并發(fā)展防酸、防爆式和消氫式鉛蓄電池.
