Misunderstandings of battery maintenance
Storage Battery is a device that directly converts chemical energy into electrical energy. It is a rechargeable battery designed to recharge through a reversible chemical reaction. It usually refers to a lead-acid battery, which is a type of battery , Belongs to the secondary battery. Its working principle: When charging, use external electric energy to regenerate internal active materials, store electric energy as chemical energy, and then convert chemical energy into electric energy output when it needs to be discharged, such as cell phone batteries commonly used in life.
Batteries are now being used more and more widely because of various advantages and some reasons, but many people don’t know the batteries very well, and even many people don’t know that some of the battery maintenance problems are still half-knowledge, and other industrial equipment. Similarly, batteries require regular maintenance. What are the common misunderstandings about battery maintenance? How much do you know about this? Today, the editor of Zhengzhou Kanglida Electronic Power Supply Co., Ltd. will give you some knowledge on this issue, and hope it will help you.
1. "Maintenance-free lead-acid batteries" do not require regular maintenance
The so-called "maintenance-free" means that compared with traditional open batteries, there is no need to add electrolyte or distilled water on a regular basis, rather than regular inspections of their ‘health’. If these maintenance-free batteries are not regularly inspected, it is very prone to deterioration and failure. From leakage to corrosion, internal short circuit, to severe, it will cause local fire and cause fire.
What are the common misunderstandings about battery maintenance?
2. Maintaining the battery only needs to monitor the voltage
Due to cost factors, some engineers often use a multimeter to test the float voltage of the battery. Currently, online systems on the market also monitor and evaluate the health of the backup battery or energy storage battery through the battery voltage. However, the float voltage can only reflect whether the charger is working normally, but it cannot reflect the health of the battery. When the battery capacity drops, the float voltage is likely to remain falsely high due to the control of the UPS charger. This is why in many cases the voltage of the UPS is displayed normally, but the battery pack is quickly powered off after a power failure and cannot be discharged.
The open circuit voltage of the battery (the voltage after disconnecting the charger) can reflect the capacity of the battery to a certain extent. However, it can be seen from the above figure that only when the battery capacity drops severely, the open circuit voltage will change significantly. The internal resistance of the battery changes much faster, and the internal resistance will increase significantly in the middle and early stages of capacity decline. Therefore, the internal resistance detects battery deterioration earlier than the voltage.
Three, a multimeter is enough to measure the internal resistance of the battery
There are three reasons why you cannot use a multimeter to measure the internal resistance of a battery:
1. Method-As we all know, multimeter measurement of resistance is based on Ohm's law, which only applies to metal conductors. But the battery is a chemical battery, and its internal chemical reaction cannot be calculated by Ohm's law, so the internal resistance measured by a multimeter has no reference significance. There are basically three methods for measuring the internal resistance of a battery: AC injection to measure internal resistance, AC discharge to measure conductivity, and DC internal resistance to discharge. It is recommended that engineers use professional instruments to accurately and reliably test the internal resistance of the battery.
2. Accuracy——The internal resistance of the battery is generally at the milliohm level, but the resistance range of an ordinary multimeter has a resolution of about 0.1Ω, which does not meet the test accuracy requirements.
3. Safety——The resistance profile of the multimeter does not allow voltage to be present on the measured object, but there is always voltage at both ends of the battery. Using a multimeter to test the internal resistance of the battery can easily burn the multimeter.
Fourth, the battery voltage is low, no need to pay attention to the safety level of the test equipment
According to the International Electrotechnical Commission IEC61010-2-030 standard, the battery test environment belongs to the CATIII electrical environment. Since the UPS or DC panel is not completely isolated from the mains, the instantaneous high-voltage shock in the power grid (due to lightning strikes or switching of the capacitor cabinet, etc.) may be transmitted to the battery terminal and cause personal injury to the tester. Therefore, please use a battery internal resistance tester of at least CATIII 600V. The concept of CAT grade is not alarmist. Its design requirements ensure that there is sufficient creepage distance between the exposed metal part of the meter and the human hand when the test probe is subjected to instantaneous high voltage impact.
There will be no significant changes in the float voltage during the initial and mid-term deterioration of the battery. It is not possible to detect the problem through voltage detection until the battery is open or short-circuited or the deterioration is severe, but it may be too late.
The above is summarized by the editor of the battery manufacturer Zhengzhou Kanglida Electronic Power Co., Ltd. I hope it will be helpful to you. If you want to know more, you can follow our official website to view more information, or call directly We consult related issues.
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