Heating circuit for battery pack at low temperature and battery pack
By designing a heating circuit at low temperature of the battery pack, the PTC heating plate is charged and heated with a charging capacitor, and providing a starting current, it solves the problem of battery failure to discharge and charger overcurrent protection in low temperature environments, and achieves the normal operation of the battery pack in low temperature environments and the charging rate increase.
Patent Information
- Application Number
- CN202420643875.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-03-29
- Publication Date
- 2025-05-06
- Estimated Expiration
- 2034-03-29
AI Technical Summary
In a low temperature environment, the battery cannot be discharged, resulting in the PTC heating plate being unable to heat. At the same time, the impact current of the PTC heating plate is relatively large, which can easily trigger the overcurrent protection of the low-power charger and affect the charging rate.
Design a heating circuit at low temperature of the battery pack, including a power supply module, a charging module and a PTC heating plate. The power supply module charges and heats the PTC heating plate through a charging capacitor, and provides a starting current through a charging capacitor during the charging process to avoid overcurrent protection of the charger.
It realizes that the battery pack can work normally in low-temperature environments, and improves compatibility with low-power chargers, avoids overcurrent protection caused by inrush current, and improves charging rate.
Smart Images
Figure CN222839824U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of batteries, in particular to a heating circuit for a battery pack at low temperature and a battery pack. Background Art
[0002] At present, the development of new energy is in full swing. Batteries are present in both smart homes and electric vehicles.
[0003] In the related art, batteries cannot be discharged at temperatures below -20 degrees Celsius, and the PTC heater in the battery pack cannot be turned on to heat it. At the same time, the impact current of the PTC heater is large at low temperatures, which can easily trigger overcurrent protection for low-power chargers, thereby affecting the charging rate. Utility Model Content
[0004] The purpose of the utility model is to overcome the shortcomings of the prior art and provide a low-temperature heating circuit and a battery pack, which can enable the battery pack to be used in a low-temperature environment and have stronger compatibility with low-power chargers, and will no longer cause overcurrent protection due to impact current.
[0005] The purpose of this utility model is achieved through the following technical solutions:
[0006] A first aspect of the present application provides a heating circuit for a battery pack at low temperatures and a battery pack, comprising: a power module; a charging module, the charging module comprising a charging capacitor, the charging capacitor being electrically connected to the power module; and a PTC heating plate, the PTC heating plate being electrically connected to the charging capacitor.
[0007] The power module includes a battery and a first switch, the battery is electrically connected to a first end of the first switch, and a second end of the first switch is electrically connected to the charging capacitor.
[0008] The charging module further includes a protection unit, the protection unit includes a second switch, and a first end of the second switch is electrically connected to the charging capacitor.
[0009] The protection unit further includes a pre-charging resistor, a second end of the second switch is electrically connected to a first end of the pre-charging resistor, and a second end of the pre-charging resistor is electrically connected to the battery.
[0010] The charging module further includes a third switch, a first end of the third switch is electrically connected to the charging capacitor, and a second end of the third switch is electrically connected to the battery.
[0011] It also includes a fourth switch, a first end of the fourth switch is electrically connected to the PTC heating plate, and a second end of the fourth switch is electrically connected to the second end of the third switch.
[0012] It also includes a fifth switch, a first end of which is electrically connected to the PTC heating plate.
[0013] It also includes a first charging interface, which is electrically connected to the second end of the fifth switch.
[0014] It also includes a second charging interface, which is electrically connected to the battery.
[0015] A battery pack comprises the low temperature heating circuit of the battery pack described in any one of the above embodiments.
[0016] Compared with the prior art, the utility model has at least the following advantages:
[0017] The power module charges the charging capacitor, and when the charging capacitor needs to be heated at -40℃ to -20℃, it will charge the PTC heating sheet to enable the battery pack to work in a low temperature environment. In addition, during charging and heating, the charging module and the PTC heating sheet will provide the charger with a starting current, thereby preventing the charger from being over-current protected due to the impact current of the PTC heating sheet. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings required for use in the embodiments are briefly introduced below.
[0019] Figure 1 It is a functional module diagram of a heating circuit for a battery pack at low temperature in one embodiment of the utility model;
[0020] Figure 2 FIG. 4 is a circuit diagram of a heating circuit for a battery pack at low temperature in one embodiment of the present invention. DETAILED DESCRIPTION
[0021] The embodiments of the present application will be described in more detail below with reference to the accompanying drawings. Although the embodiments of the present application are shown in the accompanying drawings, it should be understood that the present application can be implemented in various forms and should not be limited by the embodiments described herein. On the contrary, these embodiments are provided to make the present application more thorough and complete, and to fully convey the scope of the present application to those skilled in the art.
[0022] It should be understood that although the terms "first", "second", "third", etc. may be used in this application to describe various information, this information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of this application, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of this application, the meaning of "multiple" is two or more, unless otherwise clearly and specifically defined.
[0023] Unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", "fixed" and the like should be understood in a broad sense, for example, it can be a fixed connection, or a detachable connection or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to specific circumstances.
[0024] In the related art, batteries cannot be discharged at temperatures below -20 degrees Celsius, and the PTC heater in the battery pack cannot be turned on to heat it. At the same time, the impact current of the PTC heater is large at low temperatures, which can easily trigger overcurrent protection for low-power chargers, thereby affecting the charging rate.
[0025] In response to the above problems, the embodiments of the present application provide a low-temperature heating circuit and a battery pack, which can enable the battery pack to be used in a low-temperature environment while having stronger compatibility with low-power chargers and will no longer cause overcurrent protection due to impact current.
[0026] The technical solution of the embodiments of the present application is described in detail below with reference to the accompanying drawings.
[0027] See also Figure 1 A heating circuit for a battery pack at low temperature includes: a power module 100, a charging module 200 and a PTC heating plate 300; the charging module 200 includes a charging capacitor C1, and the charging capacitor C1 is electrically connected to the power module 100; the PTC heating plate 300 is electrically connected to the charging capacitor C1.
[0028] It should be noted that the charging capacitor C1 is a super capacitor, and the power module 100 not only charges the charging capacitor C1, but also supplies power to the entire circuit. Furthermore, the power module 100 charges the charging capacitor C1, and then the charging capacitor C1 will charge and heat the PTC heating plate 300 at -40℃ to -20℃, so that the battery pack can discharge in a low temperature environment. In addition, the resistance of the PTC heating plate 300 is small at low temperatures, so the PTC heating plate 300 will generate an impact current when it is started. Therefore, in order to avoid the charger from forming overcurrent protection, when using the charger to charge and heat the PTC heating plate 300, the charging capacitor C1 provides a starting current to the PTC heating plate 300 to provide a starting current to the charger, thereby avoiding the charger from being overcurrent protected due to the impact current of the PTC heating plate 300.
[0029] See also Figure 2 Specifically, the power module 100 includes a battery and a first switch, the battery is electrically connected to a first end of the first switch, and a second end of the first switch is electrically connected to a charging capacitor C1.
[0030] It should be noted that the first switch is Figure 2 In the switch 1, the first switch is connected in series with a battery, and the battery is used to charge the charging capacitor C1.
[0031] See also Figure 2 Specifically, the charging module 200 further includes a protection unit, the protection unit includes a second switch, and a first end of the second switch is electrically connected to the charging capacitor C1.
[0032] More specifically, the protection unit further includes a pre-charging resistor R1, a second end of the second switch is electrically connected to a first end of the pre-charging resistor R1, and a second end of the pre-charging resistor R1 is electrically connected to the battery.
[0033] It should be noted that the second switch is switch 2 in the figure, and the pre-charging resistor R1 plays a role of current limiting protection to prevent excessive current from damaging the circuit.
[0034] See also Figure 2 Specifically, the charging module 200 further includes a third switch, a first end of the third switch is electrically connected to the charging capacitor C1, and a second end of the third switch is electrically connected to the battery. Specifically, the heating circuit of the battery pack at low temperature further includes a fourth switch, a first end of the fourth switch is electrically connected to the PTC heating sheet 300, and a second end of the fourth switch is electrically connected to the second end of the third switch. Specifically, the heating circuit of the battery pack at low temperature further includes a fifth switch, a first end of the fifth switch is electrically connected to the PTC heating sheet 300.
[0035] It should be noted that the third switch is Figure 2 The switch 3 in the fourth switch is Figure 2The switch 4 in the figure is Figure 2 Further, the third switch is connected in series with the charging capacitor C1, the fourth switch is connected in series with the PTC heating plate 300, and the fifth switch is connected in series with the external electrical appliance.
[0036] See also Figure 2 The heating circuit of the battery pack at low temperature also includes a first charging interface, which is electrically connected to the second end of the fifth switch. The heating circuit of the battery pack at low temperature also includes a second charging interface, which is electrically connected to the battery.
[0037] It should be noted that the first charging interface is the negative pole and the second charging interface is the positive pole.
[0038] The principle of this application is described in detail below:
[0039] When the ambient temperature is between -40℃ and -20℃, the battery charges the charging capacitor C1. First, the second switch is closed, and then the first switch is closed. The other switches remain open and are charged until the voltage of the charging capacitor C1 reaches 95% of the battery voltage. When the capacity is 95%, the current is relatively stable. Further, after reaching 95% of the battery voltage, the third switch is closed, and then the second switch is opened. The first switch remains closed, and the other switches remain open to complete the charging of the charging capacitor C1. After the charging of the capacitor C1 is completed, the first switch and the second switch are controlled to be in the open state, and then the third switch and the fourth switch are closed to heat the PTC heating plate 300. At this time, the fifth switch is open.
[0040] Furthermore, in another way, when the external charger charges the charging capacitor C1, the second switch is closed first, and then the fifth switch is closed, and the other switches remain open. After charging until the capacitor voltage reaches 95% of the battery voltage, the third switch is closed, and then the second switch is opened. The first switch and the fourth switch remain open, and the fifth switch remains closed to complete the charging of the capacitor C1.
[0041] Furthermore, in another embodiment, when an external charger is used to charge and heat the PTC heating sheet 300, the third switch, the fourth switch and the fifth switch can be closed, and the first switch and the second switch are disconnected to provide a starting current to the charger, so as to avoid overcurrent protection of the charger due to the impact current of the PTC heating sheet 300, so that the entire circuit has stronger compatibility. At the same time, the low-temperature charging and heating circuit structure and logic of the present application are relatively simple, and there is no need to set the time according to different temperature curves.
[0042] In one embodiment, a battery pack includes the low temperature heating circuit of the battery pack according to any one of the above embodiments.
[0043] It should be noted that all battery packs can be equipped with the above-mentioned heating circuit to ensure operation in low temperature environments.
[0044] The scheme of the present application has been described in detail above with reference to the accompanying drawings. In the above embodiments, the descriptions of the various embodiments have their own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments. Those skilled in the art should also be aware that the actions and modules involved in the specification are not necessarily required for the present application. In addition, it can be understood that the steps in the method of the embodiment of the present application can be adjusted in order, merged and deleted according to actual needs, and the modules in the device of the embodiment of the present application can be merged, divided and deleted according to actual needs.
[0045] The embodiments of the present application have been described above, and the above description is exemplary, not exhaustive, and is not limited to the disclosed embodiments. Many modifications and changes will be apparent to those of ordinary skill in the art without departing from the scope and spirit of the described embodiments. The selection of terms used herein is intended to best explain the principles of the embodiments, practical applications, or improvements to the technology in the market, or to enable other persons of ordinary skill in the art to understand the embodiments disclosed herein.
Claims
1. A heating circuit for a battery pack at low temperature, characterized in that: include: Power module; A charging module, the charging module comprising a charging capacitor, the charging capacitor being electrically connected to the power module; A PTC heating plate is electrically connected to the charging capacitor.
2. The low temperature heating circuit of the battery pack according to claim 1, characterized in that: The power module includes a battery and a first switch, the battery is electrically connected to a first end of the first switch, and a second end of the first switch is electrically connected to the charging capacitor.
3. The low temperature heating circuit of the battery pack according to claim 2, characterized in that: The charging module further includes a protection unit, the protection unit includes a second switch, and a first end of the second switch is electrically connected to the charging capacitor.
4. The low temperature heating circuit of the battery pack according to claim 3, characterized in that: The protection unit further includes a pre-charging resistor, a second end of the second switch is electrically connected to a first end of the pre-charging resistor, and a second end of the pre-charging resistor is electrically connected to the battery.
5. The low temperature heating circuit of the battery pack according to claim 3, characterized in that: The charging module further includes a third switch, a first end of the third switch is electrically connected to the charging capacitor, and a second end of the third switch is electrically connected to the battery.
6. The low temperature heating circuit of the battery pack according to claim 5, characterized in that: It also includes a fourth switch, a first end of the fourth switch is electrically connected to the PTC heating plate, and a second end of the fourth switch is electrically connected to the second end of the third switch.
7. The low temperature heating circuit of the battery pack according to claim 6, characterized in that: It also includes a fifth switch, a first end of which is electrically connected to the PTC heating plate.
8. The low temperature heating circuit of the battery pack according to claim 7, characterized in that: It also includes a first charging interface, which is electrically connected to the second end of the fifth switch.
9. The low temperature heating circuit of the battery pack according to claim 7, characterized in that: It also includes a second charging interface, which is electrically connected to the battery.
10. A battery pack, characterized in that: A heating circuit for a battery pack at low temperature comprising the heating circuit of any one of claims 1 to 9.