电瓶原理

电瓶原理 Principle of the battery The 2009-03-16 22:09 Principle and construction of lead-acid battery .. A battery is a chemical that stores chemical energy and emits electricity when necessary. The main components of lead batteries are as follows: Anode (peroxide, PbO2) -> active substance Cathode plate (spongiform lead. Pb) - > active substance Electrolyte (dilute sulphuric acid) - > sulfuric acid (H2SO4) + water (H2O) The battery shell Isolation plate Other (fluid latch, lid, etc.) One, the principle of lead battery and movement Lead-acid batteries in the anode (PbO2) and cathode (Pb) to the electrolyte (dilute sulphuric acid), between the poles will produce 2 v power, this is according to the principle of lead-acid batteries, through the charge and discharge, anode and electrolyte will change as follows: (anode) (electrolyte) (cathode) PbO2 + 2H2SO4 plus Pb. (peroxide) (sulphuric acid) (spongy lead) (anode) (electrolyte) (cathode) PbSO4 + 2H2O + PbSO4 - > PbO2 + 2H2SO4 + Pb. Lead (lead) (water) Chemical changes in discharge When the battery is connected to an external circuit, the dilute sulfuric acid will react with the active material on the Yin and Yang plate to produce the new compound "lead sulfate". The discharge of sulfuric acid from the electrolyte, the longer the discharge, the thinner the acid concentration. If the concentration of sulfuric acid in the electrolyte is measured, then the amount of electricity or residual charge can be obtained. Chemical changes in charge Due to the discharge in the anode, cathode plate produced by the lead sulfate can be decomposed when charging back into sulfuric acid, lead and lead oxide, thus gradually increased the concentration of electrolyte, also is the proportion of the electrolyte, and back to the front of the discharge concentration gradually, these changes show the active material of battery is restored to the state of the power supply again, when the poles of the reduction of lead sulfate original active substances, which is equal to the end of charging, and the cathode plate will generate hydrogen, anode produces oxygen, charging to the last stage, almost all current used in the electrolysis of water, thus the electrolyte will reduce, at this point shall be supplemented by pure water. The construction of electric car battery Electric car battery must meet the following conditions: It was not a high-performance Resistance to shock It was not long life Maintenance is easy As a result of the accumulated multiple experimental results, the fiberglass tubular lead accumulator has many advantages. 1. The plate According to the battery capacity, choose the suitable size plate and quantity. In charge and discharge, the active material expands and contracts as the volume changes. The active substances, between the cathode plate of spongy lead strong adhesive force, and the adhesion strength of the anode lead peroxide of the weak, and therefore in charge and discharge, will slowly fall off, this is the cause of the lead battery life is limited. When the battery life is extended, it can withstand shock and shock, and the improvement of the anode is a very urgent task. Glass tube type anode plate: this is made of glass fibre hose in lead alloy of gold (rui jin) pectinate grid, between the hose and rui gold lead powder, filling the hose seal, the changing, producing active substances, due to the active substance will not fall off, also good contact with the electrolyte, is a very good plate material. Using a battery that has this plate is the only option for electric cars. Woven hose is in 9 microm (mu) of the glass fiber woven pipe pouch, good elasticity, resistant to expansion and contraction, and penetration of the electrolyte is also very good, the hose is the best products, for a long time, the practical performance is good. Mushy type plate: a paste made of dilute sulphuric acid which is coated in a plaid of lead and gold, and the active substance formed after drying. This approach has been used on the cathode plates of lead batteries and is also used in cars, minivans' batteries. 2. The isolation plate It can prevent the short circuit between the Yin and the sun plate, but it will not interfere with the flow of ionic ions. And it does not degrade or release impurities for long periods of time. Lead batteries are commonly used in the use of glia. 3. The battery shell It is highly acidic and has mechanical strength. Electric vehicle battery shell is the synthetic resin of the use of material strength through special processing, its special mechanical strength is strong, the cover is also using the same material, by hot melt then. 4. The electrolyte The proportion of the electrolyte on the basis of the value of 20 ?. When the electric vehicle battery fully charged electrolyte proportion is 1.280. 5. Vent plug The function of the nozzle is to determine the proportion of the gas and water that is produced when the charge is discharged. The capacity of the battery The capacity of the electric car battery shall be expressed as follows: When the electrolyte ratio 1.280/20 ? The current of five hours of discharge current The discharge termination voltage 1.70 V/Cell When discharge of the electrolyte temperature 30 + 2 ? The voltage of the terminal voltage in discharge is lower than before discharge, the reason is as follows: (1) V = E - I.R V: terminal voltage (V) I: discharge current (A) E: the open circuit voltage (V) R: internal impedance (Ω) (2) when discharge, the proportion of electrolyte is decreased, and the voltage is decreased. (3) when discharging, the internal impedance of the battery increases, and when fully charged, it increases by two to three times when fully charged. When used for lifting the battery voltage is lower than is used to walking, but due to the reuse of hydraulic motor than walking with the drive motor power of big, therefore put a large current, on the type of I.R also bigger. The capacity of the battery is expressed In capacity testing, the relationship between discharge rate and capacity is as follows: 5 hr... 1.7 V/cell 3 hr... 1.65 V/cell 1 hr... 1.55 V/cell Do not reach the above voltage continue to continue to discharge, discharge, battery internal temperature rise, the more serious, active material degradation and shorten battery life. Therefore, if the battery voltage of the stack is up to 1.75v/cell (24cell 42v, 12cell 21v), it should be stopped and recharged immediately. Battery temperature and capacity When the battery temperature decreases, the capacity will decrease significantly for the following reasons. (A) the electrolyte is not easily diffused, and the chemical reaction rate of the two active substances is slowed down. (B) the impedance of the electrolyte increases, the voltage of the battery drops, and the battery's 5HR capacity decreases as the battery temperature decreases. Therefore: Winter is shorter than summer. (2) in particular, the battery that is used in the freezer is large, and the actual use time of the day is significantly reduced. If you want to prolong the use of time, you should increase the temperature before the winter or the freezer. Power and life The battery life will be affected by the fact that the battery life will be low when it is used for use. Keep the electricity and the weight The electrolyte ratio of the battery is almost proportional to the charge of the battery. Therefore, the charge of the battery is calculated based on the proportion of the battery's total discharge and the weight of the 10% discharge. The best way to determine the power of a lead battery is to determine the proportion of the electrolyte. Therefore, periodically to determine the proportion of after use, in order to avoid excessive discharge, measuring the specific gravity of at the same time, the side of the electrolyte temperature, also to 20 degrees C conversion out of proportion, don't make it to 80% below the discharge value. Discharge and internal impedance Internal impedance due to discharge increases with the increase, especially the discharge end, impedance, the biggest primary because of the discharge current produces in the process of making plates poor conductor ? lead sulfate reduced and the proportion of the electrolyte, To enhance internal impedance, so after discharge, be sure to charge right away, if allowed to continue to discharge, the lead sulfate to form stable after white crystalline sulfide (this is known as the literature said phenomenon), even if charging, plate of the active material is also unable to recover, and will shorten the service life of the battery. White sulphate of white sulphate Battery discharge, the Yin and anode plate at the same time produce lead sulfate (PbS04), if allowed to continue, will not be charging, it finally can form stable white lead sulfate crystallization (even if the recharging, also difficult to restore the original active substances) this state is called white vulcanized phenomenon. Temperature in discharge When the battery overdischarge, the internal impedance increases significantly, so the battery temperature rises. Discharge when the temperature is high, the temperature will increase the charging is completed, therefore, will be at the end of the discharge temperature control under 40 ? for the ideal. Management of charging Battery charging characteristics The terminal voltage of the battery charge is expressed as follows V = E + I.R, here E = battery voltage (V) (A) R = I = charge current internal impedance (Ω) 2. The temperature and battery life Elevated temperature (temperature) electrolyte battery, the plate on the active substances can degradation, namely, Yin and Yang and the corrosion of anode grid, and shorten the battery life, in contrast, when the battery temperature is too low, will reduce batteries' storage capacity, easy to excessive discharge, thus shortening battery life. This kind of relationship will also be changed by the battery type, the plate material. Therefore, the following conditions should be observed: Often a battery electrolyte temperature should be maintained at 15 ~ 55 ? for ideal state, under the condition of forced, nor more than discharging to 15 ~ 55 ?, the range of 0 ~ 60 ? when charging. Actual use, due to the charging temperature rise, therefore, in order to maintain the electrolyte at the end of the discharge temperature below 40 ? for the ideal.