Battery maintenance for basic maintenance of electric vehicles

1. Battery use and maintenance

1. In order to ensure the service life of the battery, the battery that is put into use should be in a fully charged state; the battery that is insufficiently charged cannot be used. During use, pay close attention to the degree of discharge, and overdischarge is strictly prohibited—that is, when the voltage drops to 5.1V/unit (6.8V/unit for 8V batteries), and the electrolyte density drops to 1.17㎏/dm3, you should stop discharging and charge in time; It should not be put on hold for a long time. This kind of supplementary electricity that needs to be carried out frequently during use is called ordinary charging.

2. Ordinary charging: According to the ordinary charging current in the table, perform the initial charging method. The charged power is 130-140% of the discharged power, and the charging time is about 15 hours.

3. The normal use of the battery should avoid overcharging, but the battery in the following situations must be overcharged in an appropriate amount, that is, balanced charging.

A. "Backward battery" in the battery pack - refers to the battery whose voltage value is lower than other batteries during the charging process and the battery that has been repaired due to faults. (The positive and negative terminals of the backward battery should be connected to the positive and negative terminals of the DC power supply separately during equalization charging).

B. The normal use of the battery should be balanced and charged every 2-3 months.

C. Batteries that have not been used for a long time should be balanced and charged before use.

4. Balanced charging

A. Charge with 0.1I5A current. (I5 is the 5-hour rate capacity discharge current).

B. Charge until the voltage reaches 7.5 (V/unit) (10.0V/unit for 8V battery), and continue to charge at half the current (ie 0.05I5A) when there are bubbles in the electro-hydraulic fluid.

Two: Storage and storage of batteries

1. The battery should be stored in a clean, dry and ventilated warehouse at 5-40℃, and the effective storage period is two years. During the storage period, it must be properly kept according to the following requirements.

2. Not subject to direct sunlight, and the distance from the heat source should not be less than 2m.

3. Avoid contact with any liquid and harmful substances, and any metal impurities must not fall into the battery.

4. It is not allowed to be upside down, and must not be subjected to any mechanical impact or heavy pressure.

5. It is not allowed to store the battery with electrolyte. In special cases, it should be fully charged and the density and liquid level of the electrolyte should be high-speed to the specified value. After the storage period expires one month, it must be recharged according to the ordinary charging method.

Three: Inspection methods for common faults of electric vehicle batteries

1. Appearance inspection: inspection of appearance deformation, damage, leakage, pollution, etc.

2. Voltage measurement: first measure the total voltage, then measure the voltage of a single battery, and check whether the connection is in good condition one by one.

3. Inspection of the battery safety valve: remove the top cover, check whether there is any abnormal phenomenon such as acid around the safety valve, open the safety valve by hand, and check whether there is adhesion, looseness or damage.

4. Internal inspection of the battery:

A. Electrolyte: Visually observe the dry humidity of the electrolyte inside the battery, and use wooden strips to test for a wet feeling;

B. Check the single cell voltage of the battery to determine the "short circuit" and "open circuit" faults: the method of measuring the single cell voltage is to use a metal wire to connect the bus bar in the battery to measure;

5. Battery air tightness check: Use the air pressure test device modified by the sphygmomanometer to inflate the battery, the pressure is 30~40Kpa, observe whether the pressure gauge is stable, or put the battery in water to check.

Four: Inspection and treatment of electric vehicle battery leakage at night

1. There are four types of leakage:

A. It is caused by poor sealing between the upper cover and the bottom groove or cracking of the sealant due to collision;

B. It is the acid leakage of the safety valve;

C. is the acid leakage at the terminal;

D. Other parts have acid leakage.

2. Inspection and treatment method: first make a visual inspection to find out the acid leakage part. Remove the panel to see if the safety valve has signs of acid leakage, and then open the safety valve to observe whether there is flowing electrolyte inside the battery. After doing the above work, if no abnormality is found, the air tightness test should be done (put it into water to pressurize and inflate, and observe whether bubbles are generated and emerge. If there are bubbles, it means that there is acid leakage and leakage). Finally, during the charging process , observe that there is flowing electrolyte and it should be drawn out.

C. When fully charged, stop charging for 0.5 hours and then halve the current (ie 0.025I5A) for 1 hour.

D. Press d and repeat several times until the battery has bubbles violently as soon as the charger is closed.