Service life of lead-acid batteries
life
1. Discharge depth
Discharge depth is the use of the process of discharge to what extent began to stop. The life of lead-acid batteries is greatly affected by the discharge depth, and the key points of design consideration are deep cycle use, shallow cycle use or floating charge use.
Because of the weak combination of the positive active material lead dioxide itself, lead sulfate is generated when discharging, and it is restored to lead dioxide when charging. The molar volume of lead sulfate is larger than that of lead oxide, so the volume of active material expands when discharging. If a mole of lead oxide is converted to a mole of lead sulfate, the volume increases by 95%. This repeated contraction and expansion, the combination of lead dioxide particles gradually relax, easy to fall off. If only 20% of the active material of one mole of lead dioxide discharges, the degree of shrinkage and expansion will be greatly reduced, and the damage of binding force will be slow. Therefore, the deeper the discharge depth, the shorter the cycle life.
2. Over-charging degree
When overcharging occurs, a large amount of gas will precipitate out. At this time, the active material on the electrode plate will be impacted by the gas, which will promote the active material to fall off. In addition, the positive grid alloy also suffers from severe anodic oxidation and corrosion, so the battery overcharge will shorten the service life.
3. Influence of temperature
Lead-acid battery life increases with temperature. Between 10 ℃ ~ 35 ℃, every increase 1 ℃, increase about 5 ~ 6 cycle, between 35 ℃ ~ 45 ℃, higher per 1 above 25 ℃ can prolong life cycle, above 50 ℃ for negative sulfide capacity loss reduces the longevity.
Battery life increases with temperature within a certain temperature range because capacity increases with temperature. If the discharge capacity remains unchanged, the discharge depth will decrease and the solid life will be prolonged when the temperature increases.
4. Influence of sulfuric acid concentration
Although the increase of acid density is beneficial to the positive plate capacity, the self-discharge of the battery increases and the corrosion of the grid also accelerates, which also promotes the loose and falling off of lead dioxide. With the increase of acid density used in the battery, the cycle life decreases.
5. Influence of discharge current density
As the discharge current density increases, the battery life decreases, because the high current density and high acid concentration conditions promote the release of the positive lead dioxide.
Installation and debugging
(1) use tools with insulators, such as pliers. Using an uninsulated tool can cause a short circuit, heat or burn to the battery, damaging the battery.
(2) do not place the battery in an airtight room or near the fire source, or it may explode or catch fire due to the hydrogen released by the battery.
(3) do not use thinner, gasoline, kerosene or synthetic fluid to clean the battery. The use of these materials can cause the battery housing to crack, leak or catch fire.
(4) when handling batteries of 45 volts or higher, take safety precautions and wear rubber insulated gloves, or you may receive an electric shock.
(5) do not put the battery in places that may be flooded. If the battery is immersed in water, it may burn or shock someone.
(6) when removing the battery, please handle it slowly. Do not break or leak the battery.
(7) when the battery is installed on the equipment, it should be installed at the bottom of the equipment as far as possible for inspection, maintenance and replacement.
(8) do not move the battery when it is charged. Do not underestimate the weight of the battery. Careless handling may cause injury to the operator.
(9) do not cover the battery with materials that can generate static electricity. Static electricity can cause a fire or explosion.
(10) use insulating cover on battery terminals and connecting plates to prevent electric shock from injuring people.
(11) the installation and maintenance of batteries shall be carried out by qualified personnel. It may be dangerous for an unskilled person to carry out such an operation.
