Accelerated test method for constant-power cycle life of valve-regulated sealed lead-acid storage battery

Abstract

The invention relates to the technical field of valve-regulated sealed lead-acid storage batteries, in particular to a constant-power cycle life accelerated test method for a valve-regulated sealed lead-acid storage battery. Before the first circulation, standing the whole battery pack for 2 hours in an environment of 40 + / -2 DEG C; connecting the batteries in the whole group in series, performing constant-power discharge according to the total discharge power value P1 and the final voltage V1, and measuring the actual discharge time; constant-voltage current-limiting 0.1 C10 charging time is 16 hours; standing for 1 hour; testing circularly; if the actual discharge time of the last cycle is greater than or equal to 60% of the average discharge time of the initial three times of discharge, determining that the discharge test is qualified; and if the final voltage discharge voltage range of the whole group of batteries is less than or equal to 200mV, judging that the consistency of the whole group of batteries is qualified. A plurality of lead-acid storage batteries are tested in series, so that the consistency of the whole group of storage batteries can be tested and judged; the test period is shorter, and the constant power cycle life and the battery consistency of the whole group of batteries can be quickly judged; and the 10-min or 15-min short-time constant-power discharge is judged compared with the original 3-hour rate discharge.

Description

Technical Field

[0001] The invention relates to the technical field of valve-controlled sealed lead-acid batteries, in particular to a constant-power cycle life acceleration test method for valve-controlled sealed lead-acid batteries. Background Art

[0002] Valve-regulated sealed lead-acid batteries have been developed for more than 100 years and have a wide range of application scenarios, from the automotive power field to the traditional low-voltage communication field. They have the characteristics of high safety, mature technology, and stable supply chain. In the past decade, the market usage of valve-regulated sealed lead-acid batteries has increased exponentially. As the application field changes from traditional low-voltage long-term backup power to high-voltage short-term backup power, the number of batteries used in the whole group has changed from 4 12V batteries (or 24 2V batteries), that is, 48V low-voltage system to 40 12V batteries (or 240 2V batteries), that is, 480V high-voltage system. Therefore, as the number of whole groups increases exponentially, users have put forward more stringent requirements for the constant power cycle life and battery consistency of the whole group of lead-acid batteries. If a single battery lags behind during the life cycle, the backup time of the whole group of batteries will be insufficient. Therefore, it is crucial to ensure the constant power cycle life and battery consistency of the whole group of batteries and how to effectively test and judge the consistency of high-power discharge of the whole group of batteries.

[0003] The current life test of valve-regulated lead-acid batteries is generally carried out in accordance with the YD / T3427-2018 standard. It is divided into two life tests, namely floating charge life test and constant power cycle life test. Usually one battery is selected for testing. The sample size is far from meeting the actual working conditions. It can judge the life of a single battery, but cannot effectively evaluate the life of the entire battery group under actual working conditions.

[0004] The life test cycle is as long as 7 to 9 months, which is time-consuming and cannot meet the needs of fast and effective evaluation.

[0005] The backup time for traditional low-voltage application scenarios is usually 3h, 5h, or 10h, while the backup time for current high-voltage scenarios is 5 to 15min. The YD / T3427-2018 floating charge life test uses the 3-hour rate discharge capacity as the evaluation standard, which no longer meets the current high-voltage short-time backup power market demand. Summary of the invention

[0006] The technical problem to be solved by the present invention is: in order to solve the problems existing in the prior art in the above-mentioned background technology, a constant-power cycle life accelerated testing method for valve-regulated sealed lead-acid batteries is provided, which is more in line with actual working conditions by connecting multiple batteries in series, can test and judge the consistency of the entire group of batteries, and can quickly judge the constant-power cycle life of the entire group of batteries and the battery consistency.

[0007] The technical solution adopted by the present invention to solve the technical problem is: a constant power cycle life acceleration test method for a valve-controlled sealed lead-acid battery, comprising the following steps:

[0008] Step 1: The whole battery set is composed of several batteries connected in series. Before the first cycle, fully charge the whole battery set and place it at 40℃±2℃ for 2 hours;

[0009] Step 2: Perform constant power discharge of the entire battery pack according to the total discharge power value P1 and the termination voltage V1, and measure the actual discharge time;

[0010] Step 3: Constant voltage and current limiting 0.1C10 charging time 16h;

[0011] Step 4: Let stand for 1 hour;

[0012] Step 5: Step 2 to Step 4 is a cycle, cycle test; if the actual discharge time of the last cycle is ≥ 60% of the average discharge time of the initial 3 discharges, the discharge test is considered to be qualified; if the extreme difference of the final discharge voltage of the whole battery group is ≤ 200mV, the consistency of the whole battery group is considered to be qualified.

[0013] Furthermore, the entire battery pack is fully charged before step 1, the nominal weight of the sample is controlled within the range of 21.0±0.1Kg to 27.5±0.1Kg, and the internal resistance is within the range of 4.5±0.2mΩ to 6.0±0.2mΩ.

[0014] Furthermore, the time for performing constant power discharge in step 2 is 10 minutes or 15 minutes.

[0015] Furthermore, in step 2, each battery in the entire battery group is connected to a voltage collection signal line.

[0016] Furthermore, in step 1, the number of batteries in the entire battery pack is more than 20.

[0017] Furthermore, the number of cycle tests in step 6 is 60 times.

[0018] Furthermore, in step 1, the nominal voltage of each battery in the entire battery pack is 12V, and the capacity of the battery is 65Ah to 100Ah.

[0019] Furthermore, in step 2, the total discharge power value P1 is 24720W to 37920W, and the termination voltage V1 is 192V.

[0020] Furthermore, in step 2, the voltage of a single battery in the entire battery pack is 9.6V.

[0021] Furthermore, each battery in the entire battery pack in step 1 is a valve-regulated sealed lead-acid battery.

[0022] Beneficial effects of the present invention:

[0023] 1. Testing several lead-acid batteries in series is closer to the actual working conditions, and can test and judge the consistency of the entire battery group, preventing and reducing losses caused by the lagging of a single battery;

[0024] 2. The test cycle is shorter, from the original 7 to 9 months to 1 month, which can quickly judge the constant power cycle life and battery consistency of the entire battery group, and can quickly and effectively guide manufacturers to optimize the process;

[0025] 3. The short-term constant power discharge of 10 minutes or 15 minutes is more in line with the high voltage scenarios in the actual market than the original 3-hour rate discharge evaluation. DETAILED DESCRIPTION

[0026] The basic structure of the present invention is only schematically described, and therefore only the configurations relevant to the present invention are shown.

[0027] The following examples use valve-regulated sealed lead-acid batteries of the same design and manufacturing process as experimental samples, and select different example groups to conduct constant power accelerated cycle life tests at 25°C by controlling the battery weight tolerance for comparative verification.

[0028] Embodiment 1:

[0029] 20 12V65Ah valve-regulated sealed lead-acid batteries are fully charged, where the constant voltage of each battery is 14.1V and the current limit is 0.1C, that is, the voltage in series is summed and the current remains unchanged. At the same time, the battery is a battery with a default capacity qualification, the sample has a nominal weight of 21.0±0.1Kg, and an internal resistance of 6.0±0.2mΩ. According to the nominal 15min constant power discharge test, the specific cycle steps are as follows:

[0030] Step 1: Place the entire set of 20 batteries 12V65Ah in a 40℃±2℃ environment for 2 hours;

[0031] Step 2: Connect 20 batteries in series and connect a voltage acquisition signal line to each battery to collect the voltage of each battery in real time. Set the total discharge power value to 24720W and the termination voltage to 192V for constant power discharge. Record the discharge time and measure and record the voltage of each battery.

[0032] Step 3: Constant voltage 284V, current limit 6.5A, charging time 16h;

[0033] Step 4: Let stand for 1 hour;

[0034] Step 5: Step 2 to Step 4 is a cycle, and the cycle test is performed 60 times.

[0035] The discharge time of the first cycle is 16min45s, the discharge time of the second cycle is 16min57s, and the discharge time of the third cycle is 16min52s. The average discharge time of the first three times is 16min51s. The actual discharge time of the 60th cycle is 10min22s, which is greater than 60% of the average discharge time of the initial three discharges. The discharge test of the entire battery group is judged to be qualified.

[0036] Table 1: Example 1, 60th cycle, 20 battery termination voltage table

[0037] Serial number 1 2 3 4 5 6 7 8 9 10 Voltage 9.58 9.66 9.6 9.48 9.48 9.62 9.6 9.61 9.62 9.64 Serial number 11 12 13 14 15 16 17 18 19 20 Voltage 9.55 9.58 9.65 9.61 9.63 9.62 9.64 9.58 9.61 9.64

[0038] Table 1 is the termination voltage table of 20 batteries in the 60th cycle of Example 1. It can be seen that when the weight tolerance is controlled at ±0.1Kg, the lowest single battery voltage in the constant power accelerated cycle is 9.48V, and the final voltage range of the whole group of 20 batteries is 180mV, which is less than 200mV. It is judged that the consistency of the whole group of batteries is qualified.

[0039] Example 2 (counterexample):

[0040] Fully charge 20 12V65Ah valve-regulated sealed lead-acid batteries, where the constant voltage of each battery is 14.1V and the current limit is 0.1C, that is, the voltage in series is summed and the current remains unchanged. At the same time, the battery is a battery with a default qualified capacity, the sample has a nominal weight of 21.0±0.3Kg, and an internal resistance of 6.0±0.2mΩ. According to the nominal 15min constant power discharge test, the specific cycle steps are as follows:

[0041] Step 1: Place the entire set of 20 batteries 12V65Ah in a 40℃±2℃ environment for 2 hours;

[0042] Step 2: Connect 20 batteries in series and connect a voltage acquisition signal line to each battery to collect the voltage of each battery in real time. Set the total discharge power value to 24720W and the termination voltage to 192V for constant power discharge. Record the discharge time and measure and record the voltage of each battery.

[0043] Step 3: Constant voltage 284V, current limit 6.5A, charging time 16h;

[0044] Step 4: Let stand for 1 hour;

[0045] Step 5: Step 2 to Step 4 is a cycle, and the cycle test is performed 60 times.

[0046] The discharge time of the first cycle is 16min23s, the discharge time of the second cycle is 16min32s, and the discharge time of the third cycle is 16min35s. The average discharge time of the first three times is 16min30s. The actual discharge time of the 60th cycle is 9min42s, which is less than 60% of the average discharge time of the initial three discharges. The discharge test of the entire battery group is judged to be unqualified.

[0047] Table 2: Example 2, 60th cycle, 20 battery termination voltage table

[0048] Serial number 1 2 3 4 5 6 7 8 9 10 Voltage 9.62 9.61 9.61 9.6 9.58 9.34 9.80 9.64 9.62 9.28 Serial number 11 12 13 14 15 16 17 18 19 20 Voltage 9.58 9.55 9.68 9.64 9.70 9.66 9.64 9.62 9.60 9.63

[0049] Table 2 is the termination voltage table of 20 batteries in the 60th cycle of Example 2. It can be seen that when the weight tolerance is controlled at ±0.3Kg, the highest single battery voltage in the constant power accelerated cycle is 9.80V, the lowest single battery voltage is 9.28V, and the final voltage range of the whole group of 20 batteries is 520mV, which is greater than 200mV. It is judged that the consistency of the whole group of batteries is unqualified.

[0050] Embodiment 3:

[0051] 20 12V100Ah valve-regulated sealed lead-acid batteries are fully charged, where the constant voltage of each battery is 14.1V and the current limit is 0.1C, that is, the voltage of the series connection is summed and the current remains unchanged. At the same time, the battery is a battery with a default capacity qualification, the sample has a nominal weight of 27.5±0.1Kg, and an internal resistance of 4.5±0.2mΩ. According to the nominal 15min constant power discharge test, the specific cycle steps are as follows:

[0052] Step 1: Place the entire set of 20 batteries 12V100Ah at 40℃±2℃ for 2 hours;

[0053] Step 2: Connect 20 batteries in series and connect a voltage acquisition signal line to each battery to collect the voltage of each battery in real time. Set the total discharge power value to 37920W and the termination voltage to 192V for constant power discharge. Record the discharge time and measure and record the voltage of each battery.

[0054] Step 3: Constant voltage 284V, current limit 10A, charging time 16h;

[0055] Step 4: Let stand for 1 hour;

[0056] Step 5: Step 2 to Step 4 is a cycle, and the cycle test is performed 60 times.

[0057] The discharge time of the first cycle is 16min38s, the discharge time of the second cycle is 16min45s, and the discharge time of the third cycle is 16min55s. The average discharge time of the first three times is 16min46s. The actual discharge time of the 60th cycle is 10min18s, which is greater than 60% of the average discharge time of the initial three discharges. The discharge test of the entire battery group is judged to be qualified.

[0058] Table 3: Voltage table of 20 batteries in the 60th cycle of Example 3

[0059] Serial number 1 2 3 4 5 6 7 8 9 10 Voltage 9.61 9.62 9.65 9.61 9.57 9.56 9.62 9.62 9.54 9.6 Serial number 11 12 13 14 15 16 17 18 19 20 Voltage 9.6 9.57 9.64 9.58 9.61 9.62 9.57 9.58 9.62 9.61

[0060] Table 3 is the voltage table of 20 batteries in the 60th cycle of Example 3. It can be seen that when the weight tolerance is controlled at ±0.1Kg, the maximum single battery voltage in the constant power accelerated cycle is 9.65V, the minimum single battery voltage is 9.54V, and the final voltage range of the whole group of 20 batteries is 110mV, which is less than 200mV. It is judged that the consistency of the whole group of batteries is qualified.

[0061] Embodiment 4 (counterexample):

[0062] Fully charge 20 12V100Ah valve-regulated sealed lead-acid batteries, where the constant voltage of each battery is 14.1V and the current limit is 0.1C, that is, the voltage of the series connection is summed and the current remains unchanged. At the same time, the battery is a battery with a default qualified capacity, the sample has a nominal weight of 27.5±0.3Kg, and an internal resistance of 4.5±0.2mΩ. According to the nominal 15min constant power discharge test, the specific cycle steps are as follows:

[0063] Step 1: Place the entire set of 20 batteries 12V100Ah at 40℃±2℃ for 2 hours;

[0064] Step 2: Connect 20 batteries in series and connect a voltage acquisition signal line to each battery to collect the voltage of each battery in real time; set the total discharge power value to 37920W and the termination voltage to 192V for constant power discharge, record the discharge time and measure and record the voltage of each battery;

[0065] Step 3: Constant voltage 284V, current limit 10A, charging time 16h;

[0066] Step 4: Let stand for 1 hour;

[0067] Step 5: Step 2 to Step 4 is a cycle, and the cycle test is performed 60 times.

[0068] The discharge time of the first cycle is 16min32s, the discharge time of the second cycle is 16min36s, and the discharge time of the third cycle is 16min40s. The average discharge time of the first three times is 16min36s. The actual discharge time of the 60th cycle is 10min02s, which is less than 60% of the average discharge time of the initial three discharges. The discharge test of the entire battery group is judged to be unqualified.

[0069] Table 4: Voltage table of 20 batteries in the 60th cycle of Example 4

[0070] Serial number 1 2 3 4 5 6 7 8 9 10 Voltage 9.66 9.6 9.61 9.54 9.42 9.62 9.56 9.61 9.63 9.57 Serial number 11 12 13 14 15 16 17 18 19 20 Voltage 9.58 9.62 9.64 9.61 9.61 9.62 9.61 9.62 9.63 9.64

[0071] Table 4 is the voltage table of 20 batteries in the 60th cycle of Example 4. It can be seen that when the weight tolerance is controlled at ±0.3Kg, the maximum single battery voltage in the constant power accelerated cycle is 9.66V, the minimum single battery voltage is 9.42V, and the final voltage range of the whole group of 20 batteries is 240mV, which is greater than 200mV. It is judged that the consistency of the whole group of batteries is unqualified.

[0072] From the above data comparison and analysis, the lead-acid battery constant power life accelerated test method provided by the embodiment of the present invention has obvious benefits for the constant power cycle life of the whole group of lead-acid batteries and the consistency evaluation of the batteries. It can effectively and quickly complete the performance evaluation of the whole group of batteries under the actual working conditions, greatly reduce the loss of users, and can also effectively guide battery manufacturers to optimize the production process and ensure the consistency of products through this test method.

[0073] Based on the above ideal embodiments of the present invention, the relevant staff can make various changes and modifications without departing from the technical concept of the present invention through the above description. The technical scope of the present invention is not limited to the contents of the specification, and its technical scope must be determined according to the scope of the claims.

Claims

1. A constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries, characterized in that: The steps include: Step 1: The whole battery set is composed of several batteries connected in series. Before the first cycle, fully charge the whole battery set and place it at 40℃±2℃ for 2 hours; Step 2: Perform constant power discharge of the entire battery pack according to the total discharge power value P1 and the termination voltage V1, and measure the actual discharge time; Step 3: Constant voltage and current limiting 0.1C10 charging time 16h; Step 4: Let stand for 1 hour; Step 5: Step 2 to Step 4 is a cycle, cycle test; if the actual discharge time of the last cycle is ≥ 60% of the average discharge time of the initial 3 discharges, the discharge test is considered to be qualified; if the extreme difference of the final discharge voltage of the whole battery group is ≤ 200mV, the consistency of the whole battery group is considered to be qualified.

2. The constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries according to claim 1, characterized in that: Before the step 1, the whole set of batteries is fully charged, the nominal weight of the sample is controlled within 21.0±0.1Kg to 27.5±0.1Kg, and the internal resistance is 4.5±0.2mΩ to 6.0±0.2mΩ.

3. The constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries according to claim 1, characterized in that: The time for performing constant power discharge in step 2 is 10 minutes or 15 minutes.

4. The constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries according to claim 1, characterized in that: In the step 2, each battery in the entire battery group is connected to a voltage collection signal line.

5. The constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries according to claim 1, characterized in that: In step 1, the number of batteries in the entire battery pack is more than 20.

6. The constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries according to claim 1, characterized in that: The number of cycle tests in step 6 is 60 times.

7. The constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries according to claim 1, characterized in that: In step 1, the nominal voltage of each battery in the whole battery group is 12V, and the capacity of the battery is 65Ah to 100Ah.

8. The constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries according to claim 1, characterized in that: In step 2, the total discharge power value P1 is 24720W to 37920W, and the termination voltage V1 is 192V.

9. The constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries according to claim 1, characterized in that: In step 2, the voltage of a single battery in the entire battery pack is 9.6V.

10. The constant power cycle life accelerated test method for valve-regulated sealed lead-acid batteries according to claim 1, characterized in that: In the step 1, each battery in the whole battery pack is a valve-regulated sealed lead-acid battery.