A 48V platform sodium salt battery pack formation process

Abstract

A formation process for a 48V platform sodium salt battery pack, belonging to the technical field of sodium salt battery packs. In order to solve the technical problem that when the existing technology forms a 48V platform sodium salt battery pack, the rapidly rising and falling voltage and current will affect the quality of the battery; the present invention uses a small current ramp charging method to ensure the performance of the battery pack, reduce the damage to the battery pack, set the current parameters according to the characteristics of the battery pack, and avoid the rapid rise and fall of voltage and current during the charging stage through stepped current lifting and constant current and constant voltage charging, which can reserve sufficient reaction time inside the battery pack, better match the performance of the sodium salt battery without self-discharge, make the analysis of battery performance more accurate, this process solves the problems of complex criteria and scattered parameters to be measured, deletes and simplifies some meaningless steps, and selects some representative monitoring points through multiple measurements and verifications for targeted detection, and the formation process time is short.

Description

Technical Field

[0001] The present invention relates to the technical field of sodium salt battery packs, and particularly relates to a formation process for a 48V platform sodium salt battery pack. Background Art

[0002] Sodium salt battery is a kind of high-temperature sodium battery, which has stable product properties, high safety, long service life. After the production of a 48V platform sodium salt battery pack, formation is required. Formation refers to a process before the initial use of the battery, also known as the first charge. Battery formation is a very important link in the battery manufacturing process and is also one of the key steps to ensure battery quality.

[0003] The process of battery formation includes multiple steps, such as initial charging, constant current charging, constant voltage charging, etc. During the formation process, some parameters need to be controlled to fully activate the battery active substances and control the battery quality. During the battery formation process, chemical reactions will occur inside the battery. If the reaction is not sufficient, it will affect the battery performance. When the prior art forms a 48V platform sodium salt battery pack, due to the characteristics of electronic devices, the voltage and current are likely to rise and fall rapidly during the formation charging stage. However, the 48V platform sodium salt battery pack requires a certain reaction time to activate the internal chemical conductive components. The rapidly rising and falling voltage and current will affect the quality of the battery. Therefore, a more refined formation process is needed. Summary of the Invention

[0004] The purpose of the present invention is to provide a formation process for a 48V platform sodium salt battery pack, which can solve the problem that the rapidly rising and falling voltage and current affect the quality of the battery pack during the formation of the 48V platform sodium salt battery pack mentioned in the above background art.

[0005] To achieve the above purpose, the present invention provides the following technical solution: A formation process for a 48V platform sodium salt battery pack, comprising the following steps:

[0006] S1: Raise the temperature of the environment around the battery pack to 325 degrees Celsius through a heating sheet;

[0007] S2: Perform stepped charging on the 48V platform sodium salt battery pack to fully charge the battery;

[0008] S3: Discharge the fully charged 48V platform sodium salt battery pack step by step;

[0009] S4: Naturally cool the 48V platform sodium salt battery pack to room temperature;

[0010] S5: Measure the OCV value of the 48V platform sodium salt battery pack and judge whether it is within the qualified range.

[0011] Further, S2 includes the following steps:

[0012] S201: Leave the 48V platform sodium salt battery pack stationary for 1 min before the first charge.

[0013] S202: Charge the 48V platform sodium salt battery pack in a ramp manner.

[0014] S203: Charge the 48V platform sodium salt battery pack with constant current and constant voltage.

[0015] S204: Leave the 48V platform sodium salt battery pack stationary for 5 min.

[0016] Furthermore, S3 includes the following steps:

[0017] S301: Discharge the battery pack under the condition of constant current of 24A until the battery pack is discharged to 87.5% SOC.

[0018] S302: Discharge the battery pack under the condition of constant current of 24A until the battery pack is discharged to 50% SOC.

[0019] S303: Discharge the battery pack under the condition of constant current of 24A until the battery pack is discharged to 30% SOC.

[0020] S304: Discharge the battery pack under the condition of constant current of 24A until the battery pack is discharged to 0% SOC.

[0021] Furthermore, the ramp charging process in S202 is as follows: Charge with a small current, which ramps up step by step from 0.1A to 12A within 60 min, and charge to 12A in a stepped manner.

[0022] Furthermore, the constant current and constant voltage charging process in S203 is as follows: Charge the battery pack with a constant current of 12A until the working voltage reaches 56.07V, and then continue to charge with a constant voltage of 56.07V. At this time, the current will become smaller. When the current is less than or equal to 0.15A or remains at 0.15A for 10s, jump to the next step. When the capacity is greater than or equal to 255Ah, also jump to the next step. At this time, the battery pack is in a fully charged state.

[0023] Furthermore, the charging voltage in S203 shall not exceed 56.5V. If the voltage exceeds, stop charging.

[0024] Furthermore, when the discharge time in S301 is greater than or equal to 71.25 min, jump to the next step. Immediately stop the operation when the voltage is less than or equal to 42V, the current is less than 20A, or the current remains at 20A for 45s.

[0025] Further, when the discharge time in S302 is greater than or equal to 156.75 min, jump to the next step, and immediately stop the working step when the voltage is less than or equal to 42 V, the current is less than 20 A, or the current is 20 A for 45 s.

[0026] Further, when the discharge time in S303 is greater than or equal to 114 min, jump to the next step, and immediately stop the working step when the voltage is less than or equal to 42 V, the current is less than 20 A, or the current is 20 A for 45 s.

[0027] Further, when the discharge time in S304 is greater than or equal to 171 min, jump to the next step, and immediately stop the working step when the voltage is less than or equal to 42 V, the current is less than 20 A, or the current is 20 A for 45 s.

[0028] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0029] A formation process for a 48V platform sodium salt battery pack proposed by the present invention ensures the performance of the battery pack, reduces the damage to the battery pack, and has higher production reliability through a small-current ramp charging method. The current parameters are set according to the characteristics of the battery pack, and the current is increased step by step and constant current and constant voltage charging are used to avoid rapid rise and fall of voltage and current during the charging stage, which can reserve sufficient reaction time inside the battery pack and better match the performance of the sodium salt battery without self-discharge, making the analysis of battery performance more accurate. This process solves the problems of complex criteria and scattered parameters to be measured, deletes and simplifies some meaningless steps, and selects some representative monitoring points through multiple measurements and verifications for targeted detection, with a short formation working step time. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is the overall process flow chart of the present invention;

[0031] Figure 2 is the battery pack charging process flow chart of the present invention;

[0032] Figure 3 is the battery pack discharging process flow chart of the present invention;

[0033] Figure 4 is the battery pack charge and discharge process flow table of the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0034] Next, the technical solutions in the embodiments of the present invention will be clearly and completely described in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0035] As Figure 1 shown, a formation process for a 48V platform sodium salt battery pack includes the following steps:

[0036] Step 1: Use a heating sheet to raise the temperature of the environment around the battery pack to 325 °C, so that the entire charging and discharging process of the battery pack is carried out under high-temperature conditions;

[0037] Step 2: Charge the 48V platform sodium salt battery pack in a stepped manner to fully charge the battery;

[0038] Step 3: Discharge the fully charged 48V platform sodium salt battery pack in steps;

[0039] Step 4: Naturally cool the 48V platform sodium salt battery pack to room temperature;

[0040] Step 5: Measure the OCV value of the 48V platform sodium salt battery pack to determine whether it is within the qualified range. The charge state and remaining capacity of the battery pack can be inferred through the OCV value, thereby helping to monitor the state of the battery pack.

[0041] The present invention will be further described below in conjunction with embodiments.

[0042] Please refer to Figure 3 , Step 2 includes the following steps:

[0043] (1): Let the 48V platform sodium salt battery pack stand for 1 min before the first charge;

[0044] (2): Charge the 48V platform sodium salt battery pack in a ramp manner;

[0045] (3): Charge the 48V platform sodium salt battery pack with constant current and constant voltage;

[0046] (4): Let the 48V platform sodium salt battery pack stand for 5 min.

[0047] S3 includes the following steps:

[0048] (1): Discharge the battery pack at a constant current of 24A until the battery pack is discharged to 87.5% SOC;

[0049] (2): Discharge the battery pack at a constant current of 24A until the battery pack is discharged to 50% SOC;

[0050] (3): Discharge the battery pack at a constant current of 24A until the battery pack is discharged to 30% SOC;

[0051] (4): Discharge the battery pack at a constant current of 24A until the battery pack is discharged to 0% SOC.

[0052] The ramp charging process in (2) of Step 2 is as follows: Charge using a small current that ramps up from 0.1 A to 12 A in 60 minutes in a stepwise manner. Charge to 12 A in a stepped form. Through stepped charging, sufficient reaction time can be reserved, enabling the corresponding chemical characteristics of the battery internal materials to be fully activated, optimizing and enhancing the durability of the battery pack. Consequently, the lifespan, capacity, energy, etc. of the battery pack are increased, while the defective rate is reduced.

[0053] The constant current and constant voltage charging process in (3) of Step 2 is as follows: Charge the battery pack with a constant current of 12 A until the working voltage reaches 56.07 V, and then continue charging at a constant voltage of 56.07 V. At this time, the current will decrease until it jumps to the next step when the current is less than 0.15 A or remains at 0.15 A for 10 s. It also jumps to the next step when the capacity is greater than or equal to 255 Ah. At this point, the battery pack is in a fully charged state.

[0054] In (3) of Step 2, the charging voltage shall not exceed 56.5 V. If the voltage exceeds this value, charging shall stop, which can protect the battery.

[0055] In (1) of Step 3, when the discharge time is greater than or equal to 71.25 min, jump to the next step. To protect the battery, when the voltage is less than or equal to 42 V, the current is less than 20 A, or the current remains at 20 A for 45 s, immediately stop the work step. 42 V is the cut-off voltage. When the voltage is lower than 42 V, over-discharge occurs, that is, the single battery has a failure problem, and the work step needs to be stopped.

[0056] In (2) of Step 3, when the discharge time is greater than or equal to 156.75 min, jump to the next step. When the voltage is less than or equal to 42 V, the current is less than 20 A, or the current remains at 20 A for 45 s, immediately stop the work step.

[0057] In (3) of Step 3, when the discharge time is greater than or equal to 114 min, jump to the next step. When the voltage is less than or equal to 42 V, the current is less than 20 A, or the current remains at 20 A for 45 s, immediately stop the work step.

[0058] In (4) of Step 3, when the discharge time is greater than or equal to 171 min, jump to the next step. When the voltage is less than or equal to 42 V, the current is less than 20 A, or the current remains at 20 A for 45 s, immediately stop the work step. This is used to inspect the battery at each node. When a problem is detected in a certain step of the battery discharge, the subsequent detection can be stopped in a timely manner, and at the same time, the battery can be protected.

[0059] The above corresponding inspection procedures are controlled and completed by the host computer, specifically implemented through charge and discharge detection equipment.

[0060] Specifically, the formation of the 48V sodium salt battery pack is achieved through steps such as charge and discharge, cooling, and OCV detection. By means of small-current ramp charging, the performance of the battery pack is ensured, the damage to the battery pack is reduced, and the production capacity reliability is higher. The current parameters are set according to the characteristics of the battery pack. Through stepped current elevation and constant current and constant voltage charging, the rapid rise and fall of voltage and current during the charging stage are avoided, which can reserve sufficient reaction time inside the battery pack, better fit the performance of the sodium salt battery without self-discharge, and make the analysis of battery performance more accurate. This process solves the problems of complex criteria and scattered parameters to be measured, deletes and simplifies some meaningless steps, and selects some representative monitoring points through multiple measurements and verifications for targeted detection, with a short formation process time.

[0061] It should be noted that in this article, relational terms such as first and second are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the term "comprising", "including" or any other variant thereof is intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements not only includes those elements, but also includes other elements not expressly listed, or also includes elements inherent to such process, method, article or device.

[0062] As mentioned above, the above are only the preferred specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A 48V platform sodium salt battery pack formation process, characterized in that: The following steps are involved: S1: The temperature of the environment around the battery pack is raised to 325 degrees Celsius through the heating plate; S2: Step-by-step charging of the 48V platform sodium salt battery pack to fully charge the battery; S3: discharging the fully charged 48V platform sodium salt battery pack in steps; S4: Cool the 48V platform sodium salt battery pack naturally to room temperature; S5: Measure the OCV value of the 48V platform sodium salt battery pack to determine whether it is within the qualified range; S2 includes the following steps: S201: let the 48V platform sodium salt battery pack stand for 1 minute before the first charge; S202: Ramp charging of the 48V platform sodium salt battery pack; S203: charging the 48V platform sodium salt battery pack with constant current and constant voltage; S204: let the 48V platform sodium salt battery pack stand for 5 minutes; The ramp charging process in S202 is: use a small current to charge in a step-by-step manner from 0.1A to 12A within 60 minutes, and charge to 12A in a step-by-step manner.

2. A 48V platform sodium salt battery pack formation process as claimed in claim 1, characterized in that: S3 includes the following steps: S301: Discharge the battery pack at a constant current of 24A to 87.5% SOC; S302: Discharging the battery pack at a constant current of 24A to discharge the battery pack to 50% SOC; S303: Discharging the battery pack at a constant current of 24A to discharge the battery pack to 30% SOC; S304: Discharge the battery pack at a constant current of 24A to 0% SOC.

3. A 48V platform sodium salt battery pack formation process as claimed in claim 1, characterized in that: The constant current and constant voltage charging process in S203 is: use a constant current of 12A to charge the battery pack until the operating voltage reaches 56.07V, and then continue charging at a constant voltage of 56.07V. At this time, the current will become smaller until the current is less than 0.15A or it is maintained at 0.15A for 10s, and then jump to the next step. When the capacity is greater than or equal to 255Ah, it also jumps to the next step. At this time, the battery pack is fully charged.

4. A 48V platform sodium salt battery pack formation process as claimed in claim 3, characterized in that: The charging voltage in S203 must not exceed 56.5V. If the voltage exceeds this, charging will be stopped.

5. A 48V platform sodium salt battery pack formation process as claimed in claim 2, characterized in that: When the discharge time in S301 is greater than or equal to 71.25 minutes, jump to the next step, and stop the step immediately when the voltage is less than or equal to 42V, the current is less than 20A, or when it lasts at 20A for 45 seconds.

6. A 48V platform sodium salt battery pack formation process as claimed in claim 2, characterized in that: When the discharge time in S302 is greater than or equal to 156.75 min, jump to the next step, and stop the step immediately when the voltage is less than or equal to 42 V, the current is less than 20 A, or when it lasts at 20 A for 45 s.

7. A 48V platform sodium salt battery pack formation process as claimed in claim 2, characterized in that: When the discharge time in S303 is greater than or equal to 114 minutes, jump to the next step, and stop the step immediately when the voltage is less than or equal to 42V, the current is less than 20A, or when it lasts at 20A for 45 seconds.

8. A 48V platform sodium salt battery pack formation process as claimed in claim 2, characterized in that: When the discharge time in S304 is greater than or equal to 171 minutes, jump to the next step, and stop the step immediately when the voltage is less than or equal to 42V, the current is less than 20A, or when it lasts at 20A for 45s.

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