General heating circuit and method for household energy storage lithium battery equipped with inverter

Abstract

The invention discloses a general heating circuit and method for a household energy storage lithium battery equipped with an inverter. The general heating circuit comprises a lithium battery, a main relay, a heating relay, a heating sheet, an inverter and an anti-charging branch, one end of the main relay is connected with one end of the lithium battery, the other end of the main relay is connected with one end of the inverter, and the other end of the inverter is connected with the other end of the lithium battery; the heating relay and the heating sheet are connected in series, and are connected in parallel at two ends of the inverter as a whole after being connected in series; the anti-charging branch circuit is connected in parallel with two ends of the main relay; when the lithium battery needs to be heated, the universal strong charging function of the inverter is utilized to supply power to the heating film of the lithium battery, so that the temperature of the battery is increased, and the household energy storage lithium battery is in a good working state.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy storage lithium batteries or lithium battery heating, and in particular relates to a universal heating circuit and method for household energy storage lithium batteries equipped with an inverter. Background Art

[0002] Household energy storage lithium battery systems are increasingly attracting people's attention and favor. Household energy storage lithium batteries are used as home backup power storage, which solves the pain points of power outages caused by power outages and unstable city power during people's daily electricity use, and improves the comfort and economy of home electricity use.

[0003] Lithium batteries can only perform well or achieve an ideal service life within a specific operating temperature range. Lithium batteries need to be heated before use outside the specific temperature range. PTC, FPC heating film or silicone sheet is usually used to provide the corresponding voltage and current to the PTC, FPC heating film or silicone sheet to make it heat up. The heat generated by the PTC heating film or silicone sheet is transferred to the lithium battery or lithium battery module to achieve the heating effect.

[0004] The power supply for the heating medium of a lithium battery usually comes from an external power supply or from the lithium battery itself.

[0005] like Figure 1 As shown, the heating of lithium batteries can be generally performed in the following manner: when the lithium battery needs to be heated, the main relay S1 is closed, the heating relay S2 is closed, and the battery is heated by the battery itself; or when the lithium battery needs to be heated, an external power supply is provided, the main relay S1 is disconnected, the heating relay S2 is closed, and the external power supply is converted into the heating power supply required by the PTC;

[0006] The existing methods for heating the heating medium of lithium batteries have the following disadvantages:

[0007] (1) When the lithium battery needs to be heated, it is in a low-power state and cannot provide enough energy to achieve the final heating requirements;

[0008] (2) An external power source is used to provide power to the PTC to heat the lithium battery. While adding the external power source, additional interfaces related to the lithium battery are also added, which increases the complexity of the lithium battery system design and results in less than ideal system costs. Summary of the invention

[0009] Purpose of the invention: In order to solve the shortcomings of existing means of heating the heating medium of lithium batteries, the present invention proposes a universal heating circuit and method for household energy storage lithium batteries equipped with an inverter. When the lithium battery needs to be heated, the universal strong charging function of the inverter is used to power the lithium battery heating film, thereby heating the battery and putting the household energy storage lithium battery in a good working condition.

[0010] Technical solution: A universal heating circuit for household energy storage lithium battery with inverter, including: lithium battery, main relay, heating relay, heating sheet, inverter and anti-charge branch;

[0011] One end of the main relay is connected to one end of the lithium battery, the other end of the main relay is connected to one end of the inverter, and the other end of the inverter is connected to the other end of the lithium battery;

[0012] The heating relay is connected in series with the heating plate, and after being connected in series, they are connected in parallel at both ends of the inverter as a whole;

[0013] The anti-charge branch is connected in parallel at both ends of the main relay.

[0014] Furthermore, the anti-charging branch includes an anti-charging relay and an anti-charging diode, and the anti-charging relay is connected in series with the anti-charging diode.

[0015] Furthermore, it also includes a pre-charging branch, which is connected in parallel at both ends of the main relay.

[0016] Furthermore, the pre-charging branch includes a pre-charging relay and a pre-charging resistor connected in series.

[0017] The present invention also discloses a universal heating method for a household energy storage lithium battery equipped with an inverter, comprising the following steps:

[0018] Step 1: Build a heating circuit, which is the universal heating circuit of a household energy storage lithium battery equipped with an inverter disclosed above;

[0019] Step 2: Establish communication with the inverter;

[0020] Step 3: Control the main relay to disconnect and control the anti-charge branch to close;

[0021] Step 4: Control the heating relay to close;

[0022] Step 5: Send a forced charging instruction, a forced charging voltage value, and a charging limit current value to the inverter; the inverter outputs according to the forced charging instruction, the forced charging voltage value, and the charging limit current value;

[0023] Step 6: When the forced charging and heating are completed, a cancellation command for forced charging is sent to the inverter, and the heating relay is controlled to be disconnected;

[0024] Step 7: Control the main relay to close, control the anti-charge branch to disconnect, send a charge and discharge permission instruction to the inverter, and issue a charge and discharge limit current value to complete heating.

[0025] Furthermore, the strong charging voltage value meets the voltage requirements of the lithium battery and the heating plate.

[0026] Furthermore, the charging limit current value meets the power requirement of the heating plate.

[0027] Beneficial effects: Compared with the prior art, the present invention has the following advantages:

[0028] (1) The present invention utilizes the strong charging function of the inverter and, with the help of the electrical structure of the lithium battery system, enables the inverter to output heating power to achieve the effect of heating the lithium battery;

[0029] (2) The present invention provides a more novel and feasible method for heating lithium batteries based on the existing lithium battery heating technology application scheme. The forced charging function is a function designed by the inverter to prevent the lithium battery from running out of power. It almost meets the functional characteristics of all inverters, making the lithium battery system widely compatible with the inverter and realizing the method of heating lithium batteries a better general method. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 It is a schematic diagram of PTC heating connection in the prior art;

[0031] Figure 2 The utility model discloses a universal heating circuit diagram of a household energy storage lithium battery equipped with an inverter. DETAILED DESCRIPTION

[0032] The technical solution of the present invention is now further described in conjunction with the accompanying drawings and embodiments.

[0033] Embodiment 1:

[0034] like Figure 2 As shown, this embodiment proposes a universal heating circuit for a household energy storage lithium battery with an inverter, which mainly includes: a lithium battery, a main relay S1, a pre-charge relay S3, an anti-charge relay S4, a heating relay S2, a heating plate, a micro-breaker relay S5, an inverter, a shunt, a pre-charge resistor R and an anti-charge diode D; one end of the main relay S1 is connected to one end of the lithium battery, and the other end of the main relay S1 is connected to one end of the inverter, and the other end of the inverter is connected to one end of the shunt through the micro-breaker relay S5, and the other end of the shunt is connected to the other end of the lithium battery; the heating relay S2 is connected in series with the heating plate, and after the series connection, they are connected in parallel at both ends of the inverter as a whole; the pre-charge relay S3 and the pre-charge resistor R are connected in series, and after the series connection, they are connected in parallel at both ends of the main relay S1 as a whole; the anti-charge relay S4 is connected in series with the anti-charge diode D, and after the series connection, they are connected in parallel at both ends of the main relay S1 as a whole.

[0035] This embodiment uses the inverter's forced charging function to power the heating plate, thereby heating the lithium battery. The lithium battery is connected to the inverter through the main relay S1 and establishes communication with the inverter. During heating, the universal heating circuit is placed in an anti-charging state through the anti-charging branch to prevent the inverter from charging the lithium battery during heating. During heating, the heating relay S2 is turned on so that the inverter heating energy is exclusively provided to the heating plate. The inverter of this embodiment completes a series of forced charging parameter settings so that the inverter provides heating energy as required.

[0036] Embodiment 2:

[0037] This embodiment proposes a universal heating method for a household energy storage lithium battery equipped with an inverter, which mainly includes the following steps:

[0038] When the household energy storage lithium battery needs to be heated, the main relay S1 is controlled to be disconnected, the anti-charge relay S4 is closed, and the heating relay S2 is controlled to be in a closed state; the inverter initiates a forced charge, and the forced charge voltage value meets the voltage requirements of the lithium battery and the heating plate, and the charging limit current adapts to the power requirements of the heating plate;

[0039] Inverter output;

[0040] After the forced charging and heating is completed, the inverter cancels the forced charging and disconnects the heating relay S2; closes the main relay S1 and disconnects the anti-charging relay S4.

[0041] Complete a full heating cycle.

[0042] This embodiment provides a more novel and feasible method for heating lithium batteries based on the existing lithium battery heating technology application scheme. The forced charging function is an actual function of the inverter to prevent the lithium battery from being fed back. It almost meets the functional characteristics of all inverters, making the lithium battery system widely compatible with inverters and realizing lithium battery heating method a better general method.

Claims

1. A universal heating circuit for household energy storage lithium battery with inverter, characterized by: include: Lithium battery, main relay, heating relay, heating sheet, inverter and anti-charge branch; One end of the main relay is connected to one end of the lithium battery, the other end of the main relay is connected to one end of the inverter, and the other end of the inverter is connected to the other end of the lithium battery; The heating relay is connected in series with the heating plate, and after being connected in series, they are connected in parallel at both ends of the inverter as a whole; The anti-charge branch is connected in parallel at both ends of the main relay.

2. A universal heating circuit for household energy storage lithium battery with inverter according to claim 1, characterized in that: The anti-charging branch includes an anti-charging relay and an anti-charging diode, and the anti-charging relay is connected in series with the anti-charging diode.

3. A universal heating circuit for household energy storage lithium battery with inverter according to claim 1, characterized in that: It also includes a pre-charging branch, which is connected in parallel at both ends of the main relay.

4. A universal heating circuit for household energy storage lithium battery with inverter according to claim 3, characterized in that: The pre-charging branch includes a pre-charging relay and a pre-charging resistor connected in series.

5. A universal heating method for household energy storage lithium battery with inverter, characterized in that: The following steps are involved: Step 1: construct a heating circuit, wherein the heating circuit is a universal heating circuit for a household energy storage lithium battery equipped with an inverter as described in any one of claims 1 to 4; Step 2: Establish communication with the inverter; Step 3: Control the main relay to disconnect and control the anti-charge branch to close; Step 4: Control the heating relay to close; Step 5: Send a forced charging instruction, a forced charging voltage value, and a charging limit current value to the inverter; the inverter outputs according to the forced charging instruction, the forced charging voltage value, and the charging limit current value; Step 6: When the forced charging and heating are completed, a cancellation command for forced charging is sent to the inverter, and the heating relay is controlled to be disconnected; Step 7: Control the main relay to close, control the anti-charge branch to disconnect, send a charge and discharge permission instruction to the inverter, and issue a charge and discharge limit current value to complete heating.

6. A universal heating method for household energy storage lithium battery with inverter according to claim 5, characterized in that: The strong charging voltage value meets the voltage requirements of the lithium battery and the heating plate.

7. A universal heating method for household energy storage lithium battery with inverter according to claim 5, characterized in that: The charging limit current value meets the power requirement of the heating plate.

Images