Storage battery internal resistance measuring method and circuit, health status detection method and system

Abstract

The invention discloses a storage battery internal resistance measuring method. According to the invention, the storage battery internal resistance measuring method is based on heavy current millisecond pulsed discharge and includes the following steps: the storage batter generating a discharge loop which matches the capacity of the storage battery of discharge current via a design, performing a heavy current millisecond pulsed discharge, detecting in the pulsed discharge process the variation process of a terminal voltage and the discharge current of the storage battery, and based on the Ohm law, calculating the internal resistance of the storage battery. The method can accurately measure the internal resistance of the storage battery on-line.

Description

technical field [0001] The invention relates to the technical field of storage battery detection. Background technique [0002] In addition to power generation equipment, batteries are currently the most important form of power supply. The application of batteries can be divided into three links: battery charging links, battery health status detection links, and battery power supply links. For the charging link and power supply link, there are already very mature technologies and equipment. However, there is a lack of reliable, economical, and online dynamic detection methods for battery health diagnosis. [0003] The storage battery has the advantages of stable voltage, reliable power supply, and convenient movement. It is widely used in power plants, substations, communication systems, electric vehicles, aerospace and other departments. Batteries are divided into two categories: acidic batteries (ie, lead-acid batteries) and alkaline batteries. Since the single-cell vol...

AI Technical Summary

Problems solved by technology

[0006] 1. The battery is in a floating charge state for a long time, and it is only put into operation when the power system is cut off. Since the lead-acid battery is not discharged for a long time, the surrounding electrodes are "sieged" by hydrogen bubbles, resulting in "passivation", which cannot guarantee effective energy replenishment and The large internal resistance cannot provide reliable power supply during working discharge, which may lead to the failure of the operating power supply at critical moments or the maintenance time of the battery output is much shorter than the design time;

[0007] 2. There is no online and economical monitoring method for the "health" status of the battery. The current method is: manually measure the terminal voltage of the battery one by one, and check the health status of the battery. This method is neither reliable nor timely, and the workload is huge , especially for batteries with voltage but abnormal internal resistance that cannot output the design current and cannot be detected in time. Therefore, frequent and periodic maintenance is required for the battery, which is blind. When an abnormality occurs, it is also an "emergency maintenance mode". ;

[0008] 3. Since the floating charging of multiple batteries connected in series is the main working mode of the current power supply or backup power supply, its biggest disadvantage is that it cannot take care of the characteristic differences between different batteries. In the same floating charging in series, due to the internal resistance of each battery The difference between different batteries, those with larger internal resistance cannot fully "reduce the reaction" under the same floating charge current, resulting in the rapid increase of the internal resistance of individual poor-quality batteries, which are prone to failure and reduce the reliability of the entire system;

[0010] 5. A 100% redundant battery pack is required as a backup for abnormal emergencies. The number of batteries needs to be doubled and the investment increased. However, the service life of the battery packs leaving the factory during the same period will not be improved, and the doubling of investment does not significantly improve the overall reliability of the system. The maintenance workload is also doubled;

[0011] 6. The switching power supply equipment in the floating charge mode consumes a lot of power and needs fan cooling, which is not environmentally friendly. Moreover, the switching power supply equipment and the battery pack are in the same room. When the air conditioning system or ventilation system fails, the flammable gas generated by the charging and discharging of the battery There is a greater fire hazard;

[0012] 7. Lack of advanced battery intelligent management technology and general equipment, the state of each battery of the DC backup power supply cannot form the Internet of Things through the network, complete the comprehensive coverage of measurement and control, and abnormal prediction, and the remote massive DC backup power supply cannot be realized in the monitoring center Online status diagnosis and realization of "administrative maintenance"

Images