Method for complete recovery of residual capacity of a battery to be scrapped and device therefor

Abstract

The application is suitable for a method and device for completely recycling residual power of a battery to be scrapped, and belongs to the field of new energy battery recycling. The application designs a method for completely recycling residual power of a battery to be scrapped, which specifically comprises the following steps: performing voltage sorting on the battery, and connecting batteries with the same voltage V in series; charging the energy storage battery B by the battery Bn, and stopping discharging when VnVa; boosting the voltage Vn of the battery Bn, and continuing to charge the energy storage battery B by the battery Bn, and stopping boosting when VsVa; connecting the battery Bn, the adjustable DC power supply and the energy storage battery B in series, and continuing to charge the energy storage battery B; when the circuit voltage Vs3Va, the actual voltage Vn of the power supply Bn does not have the condition of continuing to discharge, until the series connection battery voltage Vn≈0, that is, the battery is completely emptied, and the power is completely recycled.

Description

TECHNICAL FIELD

[0001] The application is suitable for a method and device for completely recycling the residual power of a battery to be scrapped, and belongs to the field of new energy battery recycling. BACKGROUND

[0002] With the rapid development of new energy lithium ion batteries, the state pays attention to energy saving and environmental protection. The application range of new energy battery packs is also expanding. Currently commonly used lithium ion batteries include lithium iron phosphate and ternary lithium. With the use of the battery, some objective reasons and life factors will cause the battery to be scrapped, but at this time the battery itself still has a part of the power stored in the battery.

[0003] Under normal circumstances, direct destructive recycling will waste a large part of the energy. There is electric energy in the battery, and the destructive recycling will also cause smoke and even fire.

[0004] The current conventional battery discharge operation is to directly use a load to discharge. There is no batch voltage reduction discharge, and the discharge operation basically does not recycle the power. In order to solve the disassembly safety and fully utilize the power in the waste battery, a reasonable recycling and discharging method is needed to fully and conveniently recycle the power in the waste battery. SUMMARY

[0005] The application is suitable for a method and device for completely recycling the residual power of a battery to be scrapped, and belongs to the field of new energy battery recycling.

[0006] In order to achieve the above purpose, the application designs a method for completely recycling the residual power of a battery to be scrapped, which specifically includes the following steps,

[0007] 1) determining that the charging voltage range of the energy storage power source to be scrapped is Va-Vb, and preparing an energy storage battery B;

[0008] 2) voltage sorting the cell battery of the energy storage power source to be scrapped, and the same voltage and internal resistance is a grade;

[0009] 3) battery series combination, series connection of n batteries of the same voltage V after grading, the series connected battery is Bn, and the voltage is Vn=n*V;

[0010] 4) detecting the battery voltage Vn of Bn and judging the voltage range: Vn∈(Va-Vb);

[0011] 5) If Vn∈(Va-Vb), battery Bn charges energy storage battery B. As energy storage battery B is charged, the voltage Vn of battery Bn gradually decreases. When Vn<Va, battery Bn stops discharging.

[0012] 6) Boost the voltage Vn of battery Bn to Vs, that is, voltage Vs∈(Va-Vb), and battery Bn continues to charge the energy storage battery B;

[0013] 7) As battery Bn discharges, when voltage Vs < Va, battery Bn does not meet the voltage boost condition;

[0014] 8) Connect battery Bn in series with the adjustable DC power supply and energy storage battery B. At this time, the voltage of the series circuit is represented by Vs3∈(Va-Vb). The energy storage battery B continues to be charged while battery Bn is discharged.

[0015] 9) As the battery Bn discharges, when the circuit voltage Vs3 < Va, the corresponding power supply Bn actual voltage Vn is no longer suitable for further discharge;

[0016] 10) Place battery Bn in the area to be sorted and continue discharging other battery groups. When the number of batteries to be sorted reaches a certain number, that is, the voltage Vm∈(Va-Vb) after the batteries in the area to be sorted are reconnected in series, the battery repeats the discharge steps 5)-9) until the voltage Vn of the series batteries is ≈ 0, that is, the battery is completely discharged and the power is fully recovered;

[0017] In the method for completely recovering the remaining power of a scrapped battery, in step 4), if Vn>Vb, the battery Bn is first connected in series with a step-down circuit so that the stepped-down voltage of the battery Bn is Vn∈(Va-Vb), and then discharged according to steps 5)-9);

[0018] The method for completely recovering the residual power of a battery to be scrapped is characterized in that, in step 4), if Vn < Va, steps 6) to 9) are directly performed for discharging.

[0019] According to the method for completely recovering the remaining power of scrapped batteries, in step 8), the adjustable DC power supply is composed of a step-down circuit and a DC power supply, and the DC power supply controls the voltage sum of the series-connected battery Bn, the step-down circuit, and the DC power supply to be between Va and Vb.

[0020] According to the method for completely recovering the remaining power of a battery to be scrapped, in step 6), the battery Bn is boosted with the assistance of a boost circuit.

[0021] According to the method for completely recovering the remaining power of a battery to be scrapped, in step 1), the charging voltage range of the energy storage battery B is Va-Vb.

[0022] The application is a method for completely recovering the residual power of a battery to be discarded, and uses a device for recovering the residual power of a battery to be discarded,

[0023] The application comprises a discharge battery cabinet for connecting the batteries to be discarded in series, and can accommodate n batteries to be discarded, and the number n can be adjusted.

[0024] A voltage monitoring device is arranged to monitor the discharge voltage of the discharge battery cabinet.

[0025] The voltage discharge selection switch comprises three parallel switches, namely a discharge switch S1, a discharge switch S2 and a discharge switch S3, and a boost circuit is connected in series to the discharge switch S2, and a buck circuit is connected in series to the discharge switch S3.

[0026] The energy storage battery B is connected in series with the discharge battery cabinet, the voltage monitoring device and the voltage discharge selection switch to form a discharge circuit, and the power of the discarded batteries in the discharge battery cabinet is recovered to the energy storage battery B.

[0027] According to the device for recovering the residual power of a battery to be discarded,

[0028] The voltage monitoring device is a PLC, the discharge battery cabinet is provided with a boost circuit, the boost circuit is provided with a switch S5, and the switch S4 and a DC power supply are connected in parallel, and the on-off of the discharge switch S1, the discharge switch S2, the discharge switch S3, the switch S4 and the switch S5 is controlled by the PLC.

[0029] The application starts and controls each switch circuit by the PLC, recovers the power of the batteries, and when the voltage of the battery to be discarded approaches 0V, it is considered that the power of the battery is completely recoverable. The power of the discarded battery is fully utilized to achieve the purpose of energy saving and environmental protection. When the voltage discharge approaches zero, the energy in the battery is also basically consumed, which can avoid the safety hidden danger caused by destructive recovery. BRIEF DESCRIPTION OF DRAWINGS

[0030] Figure 1 The application is a discharge control method flow chart,

[0031] Figure 2 The application is a device for completely recovering the power,

[0032] Figure 3 The application is a voltage curve diagram in the process of the method for recovering the residual power. DETAILED DESCRIPTION

[0033] The specific content of the application will be described in detail as follows:

[0034] Before the application recovers the power of the battery to be discarded, the batteries are first sorted by type into iron lithium batteries and ternary batteries, and the power recovery of the two types of batteries is carried out respectively.

[0035] The method for completely recycling the residual power of the battery to be scrapped, as shown in the specification, specifically comprises the following steps, Figure 1

[0036] 1) Determine the charging voltage range of the energy storage power source to be scrapped as Va-Vb, and prepare an energy storage battery B, the charging voltage range of which is Va-Vb;

[0037] 2) Perform voltage sorting on the cell battery of the energy storage power source to be scrapped, and the same voltage and internal resistance are in one grade, if there are n1 number of V1 voltage, n2 number of V2 voltage, n3 number of V3 voltage, and n number of V voltage;

[0038] 3) Combine the batteries in series, and combine the batteries with the same voltage V in n grades in series, and the battery after series connection is Bn, and the voltage is Vn=n*V;

[0039] 4) Detect the voltage Vn of the battery Bn and judge the voltage range: Vn>Vb, Vn∈(Va-Vb) or Vs<Va;

[0040] 5) If Vn∈(Va-Vb), the battery Bn charges the energy storage battery B, and as the energy storage battery B charges, the voltage Vn of the battery Bn gradually decreases, and when Vn<Va, the battery Bn no longer continues to discharge;

[0041] 6) If Vn>Vb, first connect the battery Bn in series with a step-down circuit, so that the voltage Vn of the battery Bn after voltage reduction is ∈(Va-Vb), and then discharge according to step 5).

[0042] 7) If Vn<Vb, the voltage Vn of the battery Bn is boosted, and the battery Bn is boosted with the assistance of the boost circuit, and the voltage Vn is raised to Vs, i.e., the voltage Vs∈(Va-Vb), and the battery Bn continues to charge the energy storage battery B;

[0043] 8) As the battery Bn discharges, when the voltage Vs<Va, the battery Bn does not have the condition for voltage boosting;

[0044] 9) Connect the battery Bn with an adjustable DC power supply and an energy storage battery B in series, the adjustable DC power supply is composed of a step-down circuit and a DC power supply, and the DC power supply controls the voltage of the series connection of the battery Bn, the step-down circuit and the DC power supply to be between Va-Vb, at this time, the voltage of the series connection circuit represents Vs3∈(Va-Vb), and the energy storage battery B is continuously charged, and the battery Bn is discharged;

[0045] 10) As the battery Bn discharges, when the circuit voltage Vs3<Va, the actual voltage Vn of the power source Bn does not have the condition for continuous discharge;

[0046] ​11) Place battery Bn in the area to be sorted and continue discharging other battery groups. When the number of batteries to be sorted reaches a certain number, that is, the voltage Vm∈(Va-Vb) after the batteries in the area to be sorted are reconnected in series, the battery repeats the discharge steps 5)-9) until the voltage Vn of the series batteries is ≈ 0, that is, the battery is completely discharged and the power is completely recovered.

[0047] The present invention is a device for recovering the remaining power of a discarded battery, such as Figure 2 As shown, the system includes a discharge battery cabinet for serially connecting batteries to be scrapped, capable of accommodating n batteries to be scrapped, with the number n being adjustable; a voltage monitoring device for monitoring the discharge voltage of the discharge battery cabinet; and a voltage discharge selection switch comprising three switches connected in parallel: discharge switch S1, discharge switch S2, and discharge switch S3. Discharge switch S2 is also connected in series with a step-up circuit, and discharge switch S3 is connected in series with a step-down circuit. Energy storage battery B is connected in series with the discharge battery cabinet, the voltage monitoring device, and the voltage discharge selection switch to form a discharge circuit, which recycles the energy of the scrapped batteries in the discharge battery cabinet back into energy storage battery B. The voltage monitoring device is a PLC, and the discharge battery cabinet is equipped with a step-up circuit, which is equipped with a switch S5 in parallel with a switch S4 and a DC power supply. The PLC controls the on / off of discharge switches S1, S2, S3, S4, and S5.

[0048] Specifically, according to Figure 2 The circuit diagram shown in Figure 3 The charge and discharge voltage curve is explained as follows:

[0049] 1) For a battery series combination, close switch S5 and connect n batteries of the same type and voltage (V) in series. The resulting battery is Bn, and its voltage is Vn = n * V. The voltage Vn of battery Bn belongs to the charging voltage of battery B (Va - Vb), i.e., Vn∈(Va - Vb).

[0050] 2) The PLC detects the voltage signal of battery Bn. The PLC detects the Bn battery voltage Vn and determines the voltage: Vn>Vb; Vn∈(Va-Vb); Vn<Va.

[0051] 3) If Vn∈(Va-Vb), PLC detects Vn signal, PLC issues command to close switch S1, battery Bn charges battery B, such as Figure 3 In the figure, curve C1 shows the voltage change process of battery Bn during the discharge process; curve C4 shows the voltage change process of battery B during the charging process. As battery B is charged, the voltage Vn of battery Bn gradually decreases. When Vn < Va, that is, Vn = P1, battery Bn no longer discharges.

[0052] 4) When Vn < Va, i.e. at point P1, the PLC detects the signal Vn = P1, and issues the command S1 open, S2 close, the boost circuit starts, the voltage Vn of the battery Bn is raised from P1 to P2 (Note: At this time, the voltage is the overall circuit voltage with the assistance of the boost circuit, not the actual voltage of the battery Bn. At this time, the actual voltage of the battery Bn is still Vn = P1, and the voltage of the boost circuit is denoted by Vs, i.e. Vs = xVn = P2, i.e. the voltage Vs ∈ (Va-Vb), the battery Bn continues to charge the battery B, as shown in Figure 3 Curve C2, the battery Bn discharges with the assistance of the boost circuit, and the actual voltage Vn of the battery Bn is from P1 to P4. As the battery Bn discharges, when the voltage Vs < Va, the actual voltage Vn of the battery Bn is at point P4, at which time the battery Bn does not have the boost condition. S2 is opened, and S3 is closed.

[0053] 5) The PLC opens switch S2 and closes switch S3, starts the adjustable DC power supply, opens switch S5 and closes switch S4, and the adjustable DC power supply is connected in series with the battery Bn. After the series connection, the voltage is raised from P3 to P5, at which time the circuit voltage is denoted by Vs3 ∈ (Va-Vb), as shown in Figure 3 Curve C3 discharging process, corresponding to the actual voltage P4-P6 of the battery Bn.

[0054] 6) As the power supply Bn discharges, when the circuit voltage Vs3 < Va, i.e. at point P7, the actual voltage Vn of the power supply Bn is at point P6, at which time the power supply Bn does not have the condition to continue discharging. The battery Bn is placed in the sorting area, and other batteries are discharged. When the number of batteries in the sorting area reaches a certain number, i.e. after the batteries in the sorting area are connected in series, the voltage Vm ∈ (Va-Vb), the battery repeats steps 3)-5). Until the voltage Vn of the series-connected batteries is approximately 0, i.e. the battery is completely discharged, and the C5 curve is the voltage of one battery (1 / n) in the series-connected batteries, which changes with the voltage of the series-connected battery Bn. When the C1 curve approaches 0V, i.e. the C5 curve approaches 0V, the power is completely recovered.

[0055] If Vn > (Va-Vb), first close S3 to start the step-down circuit, so that the voltage Vn of the battery Bn after being stepped down ∈ (Va-Vb), and then execute steps 3)-5).

[0056] If Vn < (Va-Vb), first close S2 to start the boost circuit, so that the voltage Vn of the battery Bn after being boosted ∈ (Va-Vb), and then execute steps 3)-5).

[0057] The application starts and controls each switch circuit through the PLC, recovers the electric quantity of the battery, and considers that the electric quantity of the battery is completely recoverable when the voltage of the battery to be scrapped approaches 0V. The electric energy of the scrapped battery is fully utilized, and the purposes of energy saving and environmental protection are achieved. When the voltage discharge approaches zero, the energy in the battery is also basically consumed, and the safety hidden danger caused by destructive recovery can be avoided.

Claims

1. A method for completely recovering the remaining power of discarded batteries, characterized by: Specifically, it includes the following steps: 1) Determine that the charging voltage range of the energy storage power supply to be scrapped is Va - Vb, and prepare the energy storage battery B; 2) Perform voltage sorting on the core batteries of the energy storage power supply to be scrapped, and batteries with the same voltage and internal resistance are in one category; 3) Battery series combination, connect n batteries with the same voltage V after sorting in series, and the battery after series connection is Bn, and the voltage is Vn = n * V; 4) Detect the voltage Vn of the Bn battery and judge the voltage range: Vn ∈ (Va - Vb); 5) If Vn ∈ (Va - Vb), the battery Bn charges the energy storage battery B. As the energy storage battery B is charged, the voltage Vn of the Bn battery gradually decreases. When Vn < Va, the battery Bn stops discharging; 6) Boost the voltage Vn of the battery Bn to Vs, that is, the voltage Vs ∈ (Va - Vb), and the battery Bn continues to charge the energy storage battery B; 7) As the battery Bn discharges, when the voltage Vs < Va, the battery Bn does not have the condition for boosting voltage; 8) Connect the battery Bn in series with the adjustable DC power supply and the energy storage battery B. At this time, the voltage of the series circuit is Vs3 ∈ (Va - Vb), continue to charge the energy storage battery B, and at the same time the battery Bn discharges; 9) As the battery Bn discharges, when the circuit voltage Vs3 < Va, the actual voltage Vn of the corresponding power supply Bn does not have the condition for continuous discharge; 10) Put the battery Bn into the area to be sorted, and continue to discharge other battery groups. When the number of batteries to be sorted reaches a certain number, that is, when the voltage Vm of the batteries in the area to be sorted after re - series connection ∈ (Va - Vb), the battery repeats the discharging steps of 5) - 9) until the series battery voltage Vn ≈ 0, that is, the battery is completely emptied and the power is completely recovered; The method for completely recovering the remaining power of the battery to be scrapped is characterized in that in step 4), if Vn > Vb, first connect the battery Bn in series with a voltage - reducing circuit to make the voltage Vn of the battery Bn after voltage reduction ∈ (Va - Vb), and then perform discharging according to steps 5) - 9); The method for completely recovering the remaining power of the battery to be scrapped is characterized in that in step 4), if Vn < Va, directly perform discharging according to steps 6) - 9).

2. The method for completely recovering the remaining power of scrapped batteries according to claim 1, characterized in that: In step 8), the adjustable DC power supply consists of a voltage - reducing circuit and a DC power supply, and the DC power supply controls the voltage of the series connection of the battery Bn, the voltage - reducing circuit and the DC power supply to be between Va - Vb.

3. The method for completely recovering the remaining power of scrapped batteries according to claim 1, characterized in that: In step 6), the battery Bn is boosted with the assistance of a boosting circuit.

4. The method for completely recovering the remaining power of scrapped batteries according to claim 1, characterized in that: In step 1), the charging voltage range of the energy storage battery B is Va - Vb.

5. A device for recovering the remaining power of a battery to be scrapped used in the method for completely recovering the remaining power of a battery to be scrapped according to claim 1, characterized in that it includes a discharging battery cabinet for connecting the batteries to be scrapped in series, which can hold n batteries to be scrapped, and the number n can be adjusted and changed; a voltage monitoring device for monitoring the discharging voltage of the discharging battery cabinet; a voltage discharging selection switch, including three parallel switches, namely a discharging switch S1, a discharging switch S2, and a discharging switch S3. A lifting circuit is also connected in series on the discharging switch S2, and a voltage - reducing circuit is connected in series on the discharging switch S3; The energy storage battery B is connected in series with the discharge battery cabinet, the voltage monitoring device and the voltage discharge selection switch to form a discharge circuit, and the scrapped battery power in the discharge battery cabinet is recovered into the energy storage battery B.

6. The device for recovering residual power of discarded batteries according to claim 5, characterized in that: The voltage monitoring device is a PLC. The discharge battery cabinet is provided with a lifting circuit. A switch S5 is provided on the lifting circuit. A switch S4 and a DC power supply are connected in parallel. The on and off of the discharge switch S1, the discharge switch S2, the discharge switch S3, the switch S4 and the switch S5 are controlled by the PLC.

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