TWM532110U - Charging apparatus - Google Patents

Abstract

A charging apparatus is utilized to charge an energy storage. A charging period includes a pre-charging stage, a constant current stage and a constant voltage stage. The charging apparatus includes a connection interface, a power supply unit, a voltage detection unit, a current detection unit and a control unit. The connection interface is coupled to the energy storage. The voltage detection unit is utilized to detect a storage voltage of the storage unit. The current detection unit is utilized to detect a charging current provided from the power supply unit to the storage unit. When the storage unit is charged to the constant voltage stage, the control unit modulates the power supply unit according to the present charging current, such that the charging current provided by the power supply unit descends over time in a step-shape.

Description

Charging device

The present disclosure relates to a charging device, and more particularly to a charging device having multiple charging modes.

At present, a large number of mobile devices are launched on the market, which mainly rely on rechargeable batteries that can be recharged as a power source. The duration of mobile devices is an important performance indicator. Therefore, manufacturers have introduced large-capacity battery modules. At the same time, the speed of battery charging has become an important design issue. For large-capacity battery modules, charging devices that advertise fast charging functions have begun to appear on the market.

Generally, when the rechargeable battery is charged, a certain amount of thermal energy will be generated accompanying the charging. If there is inadvertent operation or lack of design, it may cause high temperature, and even the battery may cause a fire. Especially in charging devices with a fast charging function, the safety and stability of the charging process are more important.

The present disclosure proposes a charging device for charging an energy storage element, and the charging period during the charging includes a pre-charging phase and a constant current (CC). Phase and constant voltage (CV) phase. The charging device comprises a connection interface, a power supply unit, a voltage detection unit, a current detection unit and a control unit. A connection interface is coupled to the energy storage component. The power supply unit is coupled to the connection interface. The voltage detecting unit is coupled to the connection interface for detecting a voltage stored in one of the energy storage elements. The current detecting unit is coupled to the connection interface for detecting a charging current supplied by the power supply unit to the energy storage element. The control unit is coupled to the voltage detecting unit, the current detecting unit, and the power supply unit.

When the energy storage component is charged to the fixed voltage stage, the current detecting unit returns the current charging current to the control unit, and the control unit adjusts the power supply unit according to the current charging current, so that the charging current supplied by the power supply unit is gradually decreased in a stepwise manner.

In some embodiments, the charging device further includes a switching unit coupled between the connection interface and the power supply unit. When the energy storage component is initially connected to the connection interface, the voltage detection unit detects the initial voltage of the energy storage component. At this time, the switching unit is non-conductive to isolate the connection interface from the power supply unit. The control unit adjusts the initial charging voltage of the power supply unit according to the initial voltage. After the initial charging voltage is adjusted, the control unit turns on the switching unit to transmit the initial charging voltage of the power supply unit to the energy storage element.

Accordingly, the present disclosure proposes a charging device that adjusts an initial charging voltage when the energy storage element is initially connected to the connection interface for the characteristics of charging the energy storage element to improve the surge current generated at the time of rapid charging. In addition, during the charging to the fixed voltage phase, the charging current supplied by the power supply unit is gradually stepped down to shorten the overall charging time and approach the maximum voltage at which the energy storage element is fully charged.

The above and other objects, features, advantages and embodiments of the present disclosure will become more apparent and understood.

100, 300‧‧‧Charging device

110, 310‧‧‧Voltage detection unit

120, 320‧‧‧ Current detection unit

130, 330‧‧‧Power supply unit

140, 340‧‧‧Control unit

150, 350‧‧‧Switch unit

360‧‧‧Temperature sensing unit

200‧‧‧ energy storage components

PW‧‧‧Power signal

Vbat‧‧‧ storage voltage

Cpw‧‧‧Charging current

Tbat‧‧‧ operating temperature

N+‧‧‧ first connection

N-‧‧‧second connection

Vpw‧‧‧Charging voltage

dV‧‧‧voltage difference

Vb1, Vb2‧‧‧ initial voltage

Vc1, Vc2‧‧‧ initial charging voltage

Cfloat‧‧‧ index of reduced charging current

Clv1~Clv8‧‧‧current level

PC‧‧‧ pre-filling phase

CC‧‧‧fixed current phase

CV‧‧‧ fixed voltage stage

The above and other objects, features, advantages and embodiments of the present disclosure will be more apparent and understood. The description of the drawings is as follows: FIG. 1 is a functional block diagram of a charging device according to an embodiment of the present disclosure. FIG. 2 is a timing diagram showing voltage changes during charging of a charging device connected to an energy storage device according to an embodiment of the present disclosure; FIG. 3 is a diagram showing charging device and storage according to an embodiment of the present disclosure. A timing diagram of current changes during charging of the component connections; and FIG. 4 is a schematic diagram of a charging device in accordance with an embodiment of the present disclosure.

The following disclosure provides many different embodiments or illustrations for implementing different features of the present disclosure. The elements and configurations of the specific illustrations are used in the following discussion to simplify the disclosure. Any examples discussed are for illustrative purposes only and are not intended to limit the scope and meaning of the disclosure or its examples. In addition, the present disclosure may repeatedly recite numerical symbols and/or letters in different examples, which are for simplicity and elaboration, and do not specify the relationship between the various embodiments and/or configurations in the following discussion.

Please refer to FIG. 1 , which is a functional block diagram of a charging device 100 in accordance with an embodiment of the present disclosure. The charging device 100 is used to charge the energy storage element 200. In practical applications, the energy storage component 200 is rechargeable Rechargeable battery, such as a lithium ion battery, a nickel hydrogen battery, a nickel cadmium battery or a lead acid battery, but the disclosure is not limited thereto, and the energy storage element 200 may also be a rechargeable battery or battery. Or other equal energy storage components.

As shown in FIG. 1 , the charging device 100 includes a connection interface (the first connection end N+ and the second connection end N- as shown), the voltage detection unit 110, the current detection unit 120, the power supply unit 130, and the control. Unit 140.

In the embodiment of FIG. 1, the first connection end N+ and the second connection end N- of the connection interface are respectively coupled to the anode end and the cathode end of the energy storage element 200. In this embodiment, the charging device 100 further includes a switching unit 150 coupled between the first connection end N+ of the connection interface and the power supply unit 130. The power supply unit 130 is coupled to the connection interface via the switching unit 150 and is configured to supply the power signal PW to the energy storage element 200.

In this embodiment, the power supply unit 130 of the charging device 100 is connected to a power source (for example, a commercial power socket, a generator, or a larger capacity battery, not shown), and the power supply unit 130 includes a transformer circuit, a rectifier circuit, A power conversion component such as a power positive circuit for converting an external input power signal (for example, an AC voltage of 110 V or 220 V, but not limited thereto) provided by a power source into a power signal PW conforming to an input specification of the energy storage component 200 ( For example, the DC voltage is 5V, 9V or 15V, and the current is 1A, 1.5A or 2A, etc., but not limited thereto.

In the embodiment of FIG. 1 , the voltage detecting unit 110 is coupled to the first connection end N+ of the connection interface, and further coupled to the anode end of the energy storage element 200, and the voltage detecting unit 110 is configured to detect the energy storage element. 200 storage Press Vbat.

In the embodiment of FIG. 1 , the current detecting unit 120 is coupled to the second connecting end N− of the connection interface, and further coupled between the cathode end of the energy storage element 200 and the system ground end of the charging device 100 . The current detecting unit 120 is configured to detect the charging current Cpw passing through the energy storage element 200. Here, the charging current Cpw refers to the magnitude of the current of the power signal PW supplied from the power supply unit 130 to the energy storage element 200.

The control unit 140 is coupled to the voltage detecting unit 110, the current detecting unit 120, the power supply unit 130, and the switching unit 150. The control unit 140 determines the current state of the energy storage component 200 by using the detection result of the voltage detecting unit 110 and the current detecting unit 120. Thereby, the control unit 140 is configured to control the switching state of the switching unit 150, and output The control signal is fed back to the power supply unit 130, thereby controlling the voltage level and current magnitude of the power supply unit 130 of the output of the power supply unit 130. The manner of control of the control unit 140 will be described in detail in subsequent paragraphs.

Please refer to FIG. 2, which is a timing diagram of voltage changes during charging of the charging device 100 and the energy storage device 200 according to an embodiment of the present disclosure.

As shown in FIG. 2, when the charging device 100 charges the energy storage device 200, the charging period of the energy storage device 200 includes a precharge phase PC, a fixed current phase CC, and a fixed voltage phase CV.

In the case where the pre-charging stage PC corresponds to when the energy storage element 200 is just connected or the remaining capacity of the energy storage element 200 is low, it is generally necessary to provide a limited current magnitude to avoid damage to the energy storage element 200. Fixed current phase CC usually It is a stage of fast charging, usually providing a large voltage/current size to improve charging efficiency. The fixed voltage phase CV generally corresponds to the high or near full charge of the energy storage component 200, and generally provides a near full charge voltage and a small turbulent current to gradually fill the energy storage component 200.

Generally, as the energy storage component 200 discharges, the storage voltage Vbat of the energy storage component 200 itself gradually decreases. Taking a lithium ion battery as an example, the storage voltage Vbat of the power full is about 4.2V, and the power is close to the power. The storage voltage Vbat at the time of depletion is about 2.8V.

When the charging device 100 is initially connected to the energy storage device 200 for a period of time belonging to the pre-charging stage PC, for example, when the user just connects the line of the charging device 100 to the connecting jack of the device to be charged, the charging device 100 cannot confirm the current storage. The current remaining power state of the component 200. In some cases, the conventional charging device charges the energy storage component 200 with a fixed output voltage, such as 4.2V, with a smaller charging current, in the pre-charge phase PC after the initial connection. It is assumed that the energy storage component 200 is low in charge before charging. At the initial connection, the storage voltage Vbat of the energy storage component 200 is about 2.8V. If the 4.2V output voltage is used to charge it, the voltage difference is 1.4V. It will generate a large inrush current during initial connection, which will easily damage the battery and increase the risk of charging.

In the present disclosure, when the charging device 100 is not connected to the energy storage device 200, the control unit 140 turns off the switching unit 150, and the power supply unit 130 does not conduct between the first connection terminal N+ of the connection interface.

When the energy storage component 200 is initially connected to the connection interface, the switching unit 150 is still not turned on at this time, so the first connection end N+ of the connection interface is The power supply unit 130 is isolated. At the same time, the voltage detecting unit 110 detects the storage voltage Vbat of the energy storage element 200 through the first connection end N+. As shown in FIG. 2, it is assumed that the initial storage voltage Vbat of the energy storage element 200 detected by the voltage detecting unit 110 is the initial voltage Vb1 at the initial connection, and the initial voltage Vb1 is assumed to be 2.8V. In the present embodiment, the control unit 140 adds a predetermined minute voltage difference dV according to the initial voltage Vb1 to generate a predetermined initial charging voltage Vc1. Where Vc1=Vb1+dV. For example, the small voltage difference dV can be 0.1V or other suitable value. In this example, the initial charging voltage Vc1 can be 2.9V, which is slightly higher than the initial voltage of the energy storage element 200 by 2.8V.

The control unit 140 adjusts the power signal PW of the power supply unit according to the calculated initial charging voltage Vc1. After the adjustment of the initial charging voltage Vc1 is completed, the control unit 140 turns on the switching unit 150, and the power supply unit 130 can set the initial charging voltage Vc1 to 2.9. The power signal PW of V is supplied to the energy storage element 200.

In the above embodiment, at the initial connection, the control unit 140 can generate an initial charging voltage Vc1/Vc2 which is slightly higher than the storage voltage Vbat of the current energy storage element 200, and both have only a small voltage with the initial voltage Vb1/Vb2. The difference dV, for example, 0.1V, because the voltage difference is small, can avoid the inrush current generated at the initial connection.

Please refer to FIG. 3, which is a timing chart showing current changes during charging of the charging device 100 and the energy storage device 200 according to an embodiment of the present disclosure. As shown in FIG. 3, the above adjustment mechanism can avoid the generation of the surge current. After the PC starts for a period of time in the precharge phase, the control unit 140 can increase the charging current Cpw of the power signal PW of the power supply unit to The higher current magnitude, for example adjusted to 2A (depending on the maximum rated charge value of the energy storage component 200, is not limited to 2A). In this way, the rate of charging can be accelerated. That is to say, when the energy storage component 200 is charged to the precharge phase PC (except before and after the initial connection), the control unit 140 can adjust the charging current Cpw of the power supply unit 130 according to the maximum rated charging value of the energy storage component 200.

As shown in FIG. 2, in another embodiment, it is assumed that the initial voltage Vb2 of the energy storage element 200 detected by the voltage detecting unit 110 is 3.0V. At this time, the control unit 140 adds a predetermined amount according to the initial voltage Vb2. The minute voltage difference dV produces a predetermined initial charging voltage Vc2, and the initial charging voltage Vc2 may be 3.1V, which is slightly higher than the initial voltage of the energy storage element 200 by 3.0V. By analogy, the control unit 140 can generate a slightly higher initial charging voltage regardless of the current state of charge of the energy storage component 200.

In the pre-charging phase PC and the fixed current phase CC, the control unit 140 can adjust the power signal PW of the power supply unit according to the above embodiment manner, so that the voltage level of the power signal PW is slightly higher than the storage voltage Vbat, therefore, the power signal PW The voltage changes with time, as indicated by the charging voltage Vpw in FIG. 2, there is a fixed small voltage difference dV between the precharge phase PC and the fixed current phase CC, the charging voltage Vpw and the storage voltage Vbat.

As shown in FIG. 2, when the energy storage component 200 is charged to the fixed voltage phase CV, at this time, the storage voltage Vbat of the energy storage component 200 has gradually approached the highest rated voltage of the energy storage component 200 (eg, the energy storage component 200 is charged). The full rated voltage is 4.2V), at which point the charging device 100 charges the energy storage element 200 with a fixed output voltage. This fixed output voltage can be close to the highest rated voltage of 4.2V, such as 99.5% of 4.2V.

As shown in FIG. 3, in the fixed voltage phase CV, the control unit 140 adjusts the charging rate by the charging current Cpw of the power signal PW. During the fixed voltage phase CV, the current detecting unit 120 returns the current level of the current charging current Cpw to the control unit 140. The control unit 140 adjusts the power supply unit 130 according to the current charging current Cpw to enable the charging of the power supply unit 130. The current Cpw gradually decreases in a stepwise manner.

As shown in FIG. 3, the charging current Cpw is the current level Clv1, Clv2... to Clv8 from low to high, respectively. After entering the fixed voltage phase CV, the control unit 140 controls the power signal PW outputted by the power supply unit 130 to charge current. Cpw changes from the current level Clv8 to the current level Clv7, after a certain time interval (for example, 100 milliseconds, 1 second, 5 seconds, depending on the charging demand), and then changes from the current level Clv7 to the current level Clv6, accordingly Similarly, the charging current Cpw is gradually changed to the current level Clv1.

In the above embodiment, the current level adjustment of the charging current Cpw is sequentially decreased according to a fixed time interval, but the current level adjustment of the charging current Cpw of the present disclosure is not limited thereto. In another embodiment, after entering the fixed voltage phase CV, the control unit 140 controls the current level of the charging current Cpw according to the storage voltage Vbat detected by the voltage detecting unit 110. For example, when the storage voltage Vbat is the highest rated voltage 86% of the energy storage component 200, the control unit 140 controls the power signal PW output by the power supply unit 130, and the charging current Cpw thereof is changed from the current level Clv8 to the current level Clv7. When the storage voltage Vbat is the highest rated voltage 88% of the energy storage element 200, the control unit 140 controls the charging current Cpw to change from the current level Clv7 to the current level Clv6. When the storage voltage Vbat is the energy storage element 200 When the highest rated voltage is 90%, the control unit 140 controls the charging current Cpw to change from the current level Clv6 to the current level Clv5, and so on, and gradually changes the charging current Cpw to the current level Clv1.

Please refer to FIG. 4, which is a schematic diagram of a charging device 300 according to an embodiment of the present disclosure. Compared with the charging device 100 shown in FIG. 1 , the charging device 300 in FIG. 4 further includes a temperature sensing unit 360 for detecting an operating temperature Tbat of the energy storage component 200 , for example, a temperature sensing unit. The 360 can be a digital temperature sensing circuit, an analog temperature sensing circuit, or a thermistor plus a related measuring circuit. The operation and connection relationship between the voltage detecting unit 310, the current detecting unit 320, the power supply unit 330, the control unit 340, and the switching unit 350 of the charging device 300 are substantially similar to the detailed description of the charging device 100 in the previous embodiment. This will not be repeated. In the embodiment of FIG. 4, after entering the fixed voltage phase CV, the control unit 340 controls the current level of the charging current Cpw according to the operating temperature Tbat detected by the temperature sensing unit 360. For example, as the operating temperature Tbat is gradually increased, the control unit 340 controls the power signal PW output by the power supply unit 330, and its charging current Cpw is gradually changed from the current level Clv8 to the current level Clv1.

In general, in the fixed voltage phase CV, the charging device no longer adjusts the magnitude of the charging current, so that the charging current is determined by its free exponential drop. In this case, the charging current with a free exponential drop will be the index of Figure 3. The falling charging current Cfloat. As shown in Figure 3, the exponentially decreasing charge current Cfloat will drop rapidly as the battery approaches saturation (the voltage difference between the charge voltage and the stored voltage is reduced), and then will slow down with a smaller turbulent current. The battery is full.

As shown in Fig. 3, in the present disclosure, the voltage phase CV is fixed, and the stepped gradually decreasing charging current Cpw does not fall sharply when entering the fixed voltage phase, but the stepwise segmentation is reduced, thus Charging of the energy storage element 200 can be accomplished relatively quickly. In the above embodiment, the stepped gradually decreasing charging current Cpw and the integrated area of time (positively related to the charged electric quantity) are larger than the integrated area of the charging current Cfloat and the time which are exponentially decreased, that is, the charging current Cpw can be used. The energy storage element 200 is quickly fully charged. Furthermore, in the fixed voltage phase CV of the present disclosure, the charging voltage Vpw (as shown in FIG. 2) can be approximated to the highest rated voltage of the energy storage component 200 (eg, the maximum rating of the energy storage component 200). The voltage is 4.2V). In the practical application example, the charging voltage Vpw used when it is nearly full is about 4.175V, which is roughly 99.4% of the maximum rated voltage. That is to say, the charging device 100 of the present invention can store energy. Element 200 is charged to a state close to the state of charge saturation.

It should be added that the current level change (Clv8 to Clv1) of the eight stages is shown in Figure 3, but this disclosure is not limited to this. In practice, it can be further subdivided into more stages or It is simply divided into fewer stages, depending on actual needs. That is to say, the charging current supplied by the power supply unit is gradually decreased in a stepwise manner according to N different current levels, wherein N is a positive integer of 2 or more.

In summary, the present disclosure proposes a charging device that adjusts the initial charging voltage when the energy storage element is initially connected to the connection interface for the characteristics of charging the energy storage element to improve the surge current generated by the rapid charging moment. flow. In addition, during the charging to the fixed voltage phase, the charging current supplied by the power supply unit is gradually stepped down to shorten the overall charging time and approach the maximum voltage at which the energy storage element is fully charged.

The terms used in the entire specification and the scope of the patent application, unless otherwise specified, generally have the ordinary meaning of each term used in the field, the content disclosed herein, and the particular content. Certain terms used to describe the disclosure are discussed in the preceding paragraphs to provide additional guidance to those skilled in the art in the description of the disclosure.

"Coupling" or "connecting" as used herein may mean that two or more elements are in direct physical or electrical contact with each other, or indirectly in physical or electrical contact with each other, and "coupled" or " Connections may also mean that two or more elements operate or interact with each other. The use of the terms first, second, and third, etc., is used to describe various elements, components, regions, layers and/or blocks. However, these elements, components, regions, layers and/or blocks should not be limited by these terms.

100‧‧‧Charging device

110‧‧‧Voltage detection unit

120‧‧‧current detection unit

130‧‧‧Power supply unit

140‧‧‧Control unit

150‧‧‧Switch unit

200‧‧‧ energy storage components

PW‧‧‧Power signal

Vbat‧‧‧ storage voltage

Cpw‧‧‧Charging current

N+‧‧‧ first connection

N-‧‧‧second connection

Claims (7)

A charging device for charging an energy storage component, wherein the charging component comprises a precharging phase, a fixed current phase and a fixed voltage phase, the charging device comprising: a connection interface coupled to the An energy storage component; a power supply unit coupled to the connection interface; a voltage detection unit coupled to the connection interface for detecting a storage voltage of the energy storage component; a current detection unit coupled to the a connection interface for detecting a charging current supplied by the power supply unit to the energy storage element; a control unit coupled to the voltage detection unit, the current detection unit, and the power supply unit; wherein, when the energy storage When the component is charged to the fixed voltage stage, the current detecting unit returns the current charging current to the control unit, and the control unit adjusts the power supply unit according to the current charging current, so that the charging current is supplied by the power supply unit. It gradually decreases in a stepwise manner. The charging device of claim 1, wherein the control unit causes the power supply unit to supply a charging voltage slightly higher than the storage voltage. The charging device of claim 1, further comprising a temperature detecting unit coupled to the connection interface, wherein the temperature detecting unit is configured to detect a temperature value of the energy storage element. A charging device as claimed in claim 1, wherein the storage device When the energy component is charged to the precharge phase, the control unit adjusts the charging current of the power supply unit according to a maximum rated charging current value of the energy storage component. The charging device of claim 1, further comprising: a switching unit coupled between the connection interface and the power supply unit; wherein the voltage detection unit detects when the energy storage element is initially connected to the connection interface After measuring an initial voltage of the energy storage component, the control unit adjusts an initial charging voltage of the power supply unit according to the initial voltage, and the control unit turns on the switching unit to transmit the initial charging voltage of the power supply unit to the storage Energy component. The charging device of claim 5, wherein when the energy storage element is initially connected to the connection interface, the switching unit is non-conductive to isolate the connection interface from the power supply unit, and the control unit adjusts the initial according to the initial voltage After charging the voltage, the control unit turns the switching unit on. The charging device of claim 5, wherein the control unit sets the initial charging voltage to the initial voltage plus a predetermined voltage difference.