Storage battery has always been an essential part of construction machinery and equipment. It can supply power to on-board electrical equipment through storage battery; Drive the starting motor and drive the engine to start. Now all construction machinery and equipment are equipped with batteries (commonly known as batteries), and some of them not only have a battery. I believe many friends know the importance of batteries for excavators. Today, let's talk about the working principle, precautions and common troubleshooting of the battery.
Type of battery
Battery, scientific name: storage battery, which is a kind of equipment for storing electric energy. Batteries are widely used. In addition to being common in motor vehicles, we can often see them in the fields of power, communication and so on. Through the charging process, the battery can convert electrical energy into chemical energy and store it. When power is needed, the battery can convert the stored chemical energy into electrical energy and output it to the outside. This conversion process is reversible for the battery.
Basic principle of battery operation
Batteries can be divided into acid batteries and alkaline batteries according to the properties of electrolyte. The electrolyte of acid battery is dilute sulfuric acid solution, while that of alkaline battery is potassium hydroxide aqueous solution. Lead acid battery is commonly used in motor vehicles. Its advantages are low price and good starting performance. Its disadvantages are short service life and large volume and weight. In this paper, we mainly introduce the lead-acid battery in detail.
Batteries can be divided into the following categories according to their purpose:
1. Starting battery: mainly used for automobiles, motorcycles, diesel engines, etc.
2. Fixed battery: mainly used for communication, power plant, computer, etc.
3. Traction battery: mainly used for battery cars, such as electric bicycles, electric vehicles, etc.
Others include railway batteries and energy storage batteries.
Common automotive batteries are divided into three categories. One is ordinary lead-acid batteries. Its electrode plate is composed of lead and lead oxide, and the electrolyte is an aqueous solution of sulfuric acid. The advantages of this battery are low price and stable voltage. One is dry charged battery. The advantage of this battery is that the negative plate has high power storage capacity. If the environment is completely dry, this battery can store the power obtained within two years. When in use, just add electrolyte and wait for 20 ~ 30 minutes before it can be used directly. The other is maintenance free battery. The advantage of this battery is that it basically does not need to supplement distilled water within its service life. In addition, it also has a series of advantages such as shock resistance, high temperature resistance, small volume, small self discharge and so on. And the service life of maintenance free battery is twice that of ordinary battery, which is much higher than that of ordinary lead-acid battery.
Key points of daily use of battery
Appearance of non maintenance free battery
1. Vent holes are generally designed on the filler hole cover of the battery. These vent holes should be checked frequently during normal use and always ensure that they are unblocked. If the vent hole is not unblocked, during the charging and discharging process, the gas generated by the chemical reaction in the battery cannot be discharged in time, which will lead to the explosion of the battery and the damage of the internal structure of the battery, resulting in unnecessary losses.
2. The pole of the battery shall be kept clean, the power supply line shall be firmly connected, and the oxide at the pole and connecting wire head shall be removed in time. The author said at the beginning of the article that if the connection is not firm or the poor contact between the pole and the wiring is caused by corrosion, it will have a great impact on the charging and reduce the service life of the battery.
3. Prevent short circuit of battery. Special attention should be paid here. Metal devices must not be placed on the battery, such as pliers, wrenches, screwdrivers and other commonly used metal tools, because after the metal devices are connected with the battery pole and grounded with the metal body, a closed circuit will be formed, resulting in short circuit of the battery, burning the battery and scrapping the battery. In addition, if there is sewage or dirt on the battery, it should also be removed in time, because these sundries will also lead to short circuit of the battery and damage the battery.
4. The battery should be regularly checked for sufficient electrolyte. The insufficient electrolyte of the battery will lead to the vulcanization of the electrode plate and the reduction of the battery capacity. In addition, another important reason for plate vulcanization is the insufficient storage of the battery, which will also reduce the electrical performance and shorten the service life of the battery.
5. Daily maintenance of battery. If the battery is not used for more than one week, consider cutting off the battery. If the battery has a switch, disconnect the battery switch.
If there is no switch, the power-off sequence of the battery is: "disconnect the negative pole first and then the positive pole". The sequence of connecting the battery is: "connect the positive pole first and then the negative pole". If the battery is not used for a long time, adjust the electrolyte to the position of the standard scale line and fully charge the battery.
6. Keep it properly. Generally, it should be placed in a ventilated, dry, dark and temperature appropriate room. Here is a point to remind you that when using the battery, you must not connect the positive and negative poles of the battery incorrectly. If the connection is wrong, the most direct consequence is to burn out the generator and related electrical equipment, resulting in unnecessary losses. Finally, pay attention to the thermal insulation and heat insulation of the battery in cold and summer seasons.
The above describes how to use and maintain the battery. Next, we will talk about the charging method of the battery. The charging methods of storage battery are generally divided into constant voltage charging and constant current charging.
Charging method of storage battery and key points for daily attention
1. Constant voltage charging is to keep the charging voltage at both ends of the battery constant. This method is suitable for emergency ordinary charging, but not for initial charging and eliminating vulcanization charging.
2. Constant current charging is a method to keep the charging current of the battery constant. This method has great adaptability, but this method has a long charging time and needs to adjust the charging current frequently, which is troublesome.
The charging of storage battery generally consists of four types: initial charging, supplementary charging, eliminating vulcanization charging and preventive charging.
1. Initial charging is more important, which is related to the rated capacity and service life of the battery, so this charging must be carried out under the guidance of an experienced master.
2. Supplementary charging means that the battery should be charged after being used for a period of time to ensure that the battery has sufficient power, so as to ensure the service life of the battery.
3. Eliminating vulcanization charging is the type of charging after the vulcanization phenomenon of the electrode plate of the battery is found. It is to eliminate the vulcanization phenomenon through repeated charging with a small current, increase the capacity of the battery and restore the performance of the battery.
4. Preventive charging means that the battery often stays in a partially charged state due to insufficient charging. If it works like this for a long time, it will easily lead to the vulcanization of the electrode plate, thus damaging the service life of the battery. This kind of charging is intermittent charging by means of supplementary charging until the last time bubbles will appear within a few minutes.
Finally, it should be noted that when charging, it should be charged in strict accordance with the specifications. If any abnormality is found during charging, the fault should be eliminated before charging. In addition, when charging, open the filling hole cover to facilitate the full discharge of gas. The last point is to strictly prevent open fire, so as to avoid the reaction between open fire and the gas discharged from the battery and explosion.
Common fault causes and solutions in the use of battery
1. How can we judge that the battery is low? Generally, there are three simple judgment methods, which are also commonly used by operators. First, the starting motor does not rotate or rotates weakly; Second, the lighting is much darker than usual; Third, the horn sound is very small or does not sound. At this time, it is likely that the above symptoms are caused by insufficient battery power. Therefore, we should check the battery in time and charge it in time to ensure that the battery works in good condition.
The main reasons for the lack of battery power are: the new battery has not been charged and discharged repeatedly, and the rated capacity of the battery has not been reached during initial charging; Long term use of lights or entertainment equipment such as radio and CD when the engine speed is low; Failure of generator leads to failure of battery charging; The electrolyte density is too high or too low.
2. How can we judge that the battery discharges by itself? When the battery is fully charged and reused after a day or two, the battery shows insufficient or no power, which indicates that the battery has self discharge.
The main reasons for the self discharge of the battery are: first, the battery partition is broken down or damaged, the electrolyte is mixed with impurities such as metal powder, or there are too many deposits in the battery slot, resulting in the internal short circuit of the battery; Second, the outside of the battery is too dirty, resulting in a short circuit between the poles.
3. How to judge whether the battery is not charged? Although the battery has been charged for a long time, the voltage rises very slowly, which indicates that there is a problem in battery charging.
The main reasons for the failure of battery charging are: the connector in the charging line is loose or the connector is corroded; Rectifier failure or diode breakdown short circuit; The battery plate is vulcanized, which makes it difficult for electrolyte to penetrate into the plate and produce chemical reaction; The battery plate is damaged due to charging or discharging the battery with high current.
4. How to judge that the electrolyte loss of the battery is too fast? When the battery has just added electrolyte, the electrolyte level is not high enough, which indicates that the electrolyte loss of the battery is too fast.
The main reasons for the rapid loss of battery electrolyte: excessive evaporation of electrolyte caused by excessive charge and discharge current; The damage of the diaphragm leads to the internal short circuit of the battery or the rupture of the battery shell leads to the leakage of electrolyte.
In case of the above situations, the battery shall be diagnosed and troubleshooting in time to ensure that the battery works in a good state.
Conclusion: as an important part of construction machinery, the correct use and maintenance of battery is very necessary. It can ensure that the construction machinery is in a good working state. Especially now the construction machinery has entered the era of mechatronics, and the importance of high-efficiency and high stability battery to modern construction machinery is self-evident.
