TW201910803A - Lithium battery electric capacity detection method using compensation calculation method converts the current actual electric capacity into the current display capacitance - Google Patents

Abstract

The invention provides a lithium battery electric capacity detection method using a compensation calculation method. The method comprises the steps of estimating an initial electric capacity of a lithium battery by an open-circuit voltage method; after the initial electric capacity of the lithium battery is obtained, calculating the consumed or supplemented electricity capacity of the lithium battery by a coulomb integral method, so as to obtain a current actual electric capacity of the lithium battery; and converting the current actual electric capacity into the current display capacitance by means of a compensation counting algorithm.

Description

Lithium battery capacity detecting method using compensation calculation method

The invention relates to a battery capacity detecting method, in particular to a lithium battery capacity detecting method using a compensation calculation method.

With the advancement of technology and the rapid development of integrated circuits, many electronic devices have been downsized. In addition to the basic requirements of lightweight and portable, long-term operation has become a necessary necessity.

Moreover, these portable electronic devices (for example, mobile phones, smart phones, digital cameras, digital cameras, notebook computers, etc.) all require electricity to operate, and the source of this power is a battery (for example, a lithium battery). So how to provide enough power for today's portable electronic devices has become one of the important challenges.

Furthermore, since the charging and discharging behavior of the battery is caused by a series of chemical redox reactions, in the course of the chemical reaction, many factors directly affect the charging and discharging characteristics of the battery, for example, the ambient temperature of the battery. , battery output current size, etc.

Moreover, since different electronic devices require different battery capacities, the internal structure or composition of different battery capacities and their charging and discharging characteristics are also different. Therefore, the difficulty in battery capacity detection will increase.

Although some battery capacity detection technologies have been developed in recent years, based on cost and accuracy considerations, the battery capacity detection technology developed at present cannot provide high-accuracy battery capacitance detection. Therefore, how to provide an effective method The high-accuracy battery capacity detection method has become an important issue in the industry.

Embodiments of the present invention disclose a method for detecting a capacitance of a lithium battery, comprising: estimating an initial capacitance of a lithium battery by an open circuit voltage method; and calculating the initial capacitance of the lithium battery by a Coulomb integral method The lithium battery consumes or replenishes the capacitance to obtain the current actual capacitance of the lithium battery; and converts the current actual capacitance to the current display capacity by a compensation calculation. The current display capacity is a current capacity that is displayed to the user/consumer, wherein the compensation calculation method is USOC=previous_USOC+(M×delta_SOC), the USOC is the current display capacity, and the previous_USOC is the previous one. The current display capacity of seconds, SOC is the current actual capacity, and previous_USOC, USOC, and SOC are presented in %, where the definition of delta_SOC will be described in detail below.

In a preferred embodiment of the present invention, the open circuit voltage method measures the open circuit voltage value measured by the lithium battery in an unloaded state, and the open circuit voltage value is the initial capacitance.

In a preferred embodiment of the present invention, when the lithium battery is discharged, M=previous_USOC/SOC, M is a slope, previous_USOC is the current display capacity of the previous second, and SOC is the current actual capacitance.

In another preferred embodiment of the present invention, when the lithium battery is charged, M=(1-previous_USOC)/(1-SOC), M is a slope, and previous_USOC is the current display capacity of the previous second, and the SOC is The current actual capacitance.

In a preferred embodiment of the present invention, delta_SOC=(DC-previous_DC) / FCC, DC is the accumulated capacity that has been discharged, and previous_DC is the accumulated capacity that has been discharged until the previous second, in other words, DC and The difference between previous_DC is that the two are the accumulated capacity that has been discharged for one second, and the FCC is the full charge capacity. Wherein, since the current amount i is an instantaneous value, which is multiplied by the time value t is the capacitance value Q (ie, Q = Σi*Δt), DC is a capacitance value.

In a preferred embodiment of the invention, the full charge capacity includes the temperature factor, the current change factor, the reserved capacitance (PreservedCap), and the pre-reserved capacity (PreReservedCap).

In a preferred embodiment of the invention, the lithium battery capacitance detecting method is operated by a controller, a microcontroller, a processor or a microprocessor.

The embodiments of the present invention are described below by way of specific examples, and those skilled in the art can readily appreciate the other advantages and functions of the present invention. The invention may be embodied or applied in various other specific embodiments, and various modifications and changes may be made without departing from the spirit and scope of the invention.

It is to be understood that the structure, the proportions, the size and the like of the present invention are only used in conjunction with the disclosure of the specification, and are intended to be understood and read by those skilled in the art, and are not intended to limit the implementation of the invention. The conditions are not technically meaningful, and any modification of the structure, change of the proportional relationship or adjustment of the size should be disclosed in the present invention without affecting the effects and achievable effects of the present invention. The technical content can be covered.

As shown in FIG. 1 , an embodiment of the present invention discloses a lithium battery capacity detecting method using a compensation calculation method, which includes the following steps: Step S10: estimating an initial capacitance of a lithium battery by an open circuit voltage method; Step S20 After obtaining the initial capacitance of the lithium battery, calculating the lithium battery consumption or supplemented capacitance by the Coulomb integration method to obtain the current actual capacitance of the lithium battery; and step S30: calculating the current actual electricity by the compensation calculation method The capacity is converted to the current display capacity. The current display capacity is a current capacity that is displayed to the user/consumer, wherein the compensation calculation method is USOC=previous_USOC+(M×delta_SOC), the USOC is the current display capacity, and the previous_USOC is the previous one. The current display capacity of seconds, SOC is the current actual capacity, and previous_USOC, USOC, and SOC are presented in %.

Specifically, in accordance with a preferred embodiment of the present invention, the open circuit voltage method measures the open circuit voltage value measured by the lithium battery in an unloaded state, and the open circuit voltage value is the initial capacitance.

Furthermore, according to a preferred embodiment of the present invention, as shown in FIG. 2A and FIG. 2B, the Coulomb integration method can be calculated by using Remaining Capacity (RC) and Full Charge Capacity (FCC). The current Stat of Charge (SOC) is as follows: SOC=RC / FCC

According to a preferred embodiment of the present invention, the present invention adds a temperature factor and a current variation factor to the full charge capacity (FCC) of the battery. Therefore, the full charge capacity (FCC) of the battery can be expressed as: FCC=Qmax×Table(Qt) ×Table (Qi)–ReservedCap–PreReservedCap, and, as shown in Fig. 2B, Qmax can be expressed as: Qmax=PassedCharge / (DOD0-DOD1) where RC can be expressed as: RC = FCC - DC where Qmax is the cell factory The ideal capacity value is provided. PassedCharge is the passing current amount, DOD (Depth of Discharge) is the discharge depth, Table (Qt) is obtained experimentally at different temperatures, and Table (Qi) is obtained experimentally under different current changes. ReservedCap To preserve the capacity, and PreReservedCap to reserve the capacity in advance.

Moreover, since the temperature and current of the battery are changing all the time, the full charge capacity (FCC) of the battery will continue to change, which will also cause the current actual capacitance (SOC) to change with the full charge capacity (FCC) of the battery. And change. Therefore, the lithium battery capacity detecting method of the present invention also includes a compensation calculation method, wherein the compensation calculation method can be expressed as USOC=previous_USOC+(M×delta_SOC), wherein USOC is the current display capacity, and previous_USOC is the current display of the previous second. Capacitance, it is worth noting that previous_USOC, USOC and SOC are all presented in %. Among them, the definition of delta_SOC will be described in detail below.

According to a preferred embodiment of the present invention, when the lithium battery is discharged, M=previous_USOC/SOC, M is the slope, previous_USOC is the current display capacity of the previous second, and SOC is the current actual capacitance.

According to another preferred embodiment of the present invention, when the lithium battery is charged, M=(1-previous_USOC)/(1-SOC), M is a slope, previous_USOC is the current display capacity of the previous second, and the SOC is the current actual capacitance.

Furthermore, regarding the delta_SOC part, delta_SOC can be expressed as delta_SOC=(DC-previous_DC)/FCC, where DC is the accumulated capacity that has been discharged, and previous_DC is the accumulated capacity that has been discharged until the previous second, in other words, The difference between DC and previous_DC is that the two are the accumulated capacity that has been discharged for one second, and the FCC is the full charge capacity of the battery.

It should be noted that in accordance with another preferred embodiment of the present invention, the battery full charge capacity (FCC) may include a temperature factor, a current change factor, a reserved capacity (ReservedCap), and a pre-reserved capacity (PreReservedCap).

In a preferred embodiment of the present invention, the lithium battery capacity detecting method of the present invention can be operated by one of a controller, a microcontroller, a processor, and a microprocessor.

In summary, the preferred embodiment of the present invention discloses a lithium battery capacity detecting method, which can quickly and accurately detect lithium battery by combining open circuit voltage method, Coulomb integral method, compensation calculation method, temperature factor and current variation factor. In addition to detecting the capacitance of the lithium battery, the present invention is also applicable to detecting other forms of battery capacity.

However, the above-described embodiments are merely illustrative of the effects of the present invention, and are not intended to limit the present invention, and those skilled in the art can modify and modify the above embodiments without departing from the spirit and scope of the present invention. . In addition, the number of elements in the above-described embodiments is merely illustrative and is not intended to limit the invention. Therefore, the scope of the invention should be as set forth in the following claims.

S10, S20, S30‧‧‧ steps

112‧‧‧First wire line

113‧‧‧First via

114‧‧‧Electrical mat

120‧‧‧Electronic biosensor

1 is a flow chart of a lithium battery capacity detecting method using a compensation calculation method according to the present invention; and FIG. 2A and FIG. 2B are diagrams showing a battery discharge depth characteristic of a lithium battery capacity detecting method using a compensation calculation method according to the present invention; Graph.

Claims (7)

A lithium battery capacity detecting method using a compensation calculation method, comprising the steps of: estimating an initial capacitance of a lithium battery by an open circuit voltage method; calculating the initial capacitance of the lithium battery by a Coulomb integral method The lithium battery consumes or supplements the capacitance to obtain the current actual capacity of the lithium battery; and converts the current actual capacitance into the current display capacity by a compensation calculation method, wherein the compensation calculation method is USOC= previous_USOC+(M×delta_SOC), USOC is the current display capacity, previous_USOC is the current display capacity of the previous second, SOC is the current actual capacity, and previous_USOC, USOC and SOC are presented in %. The method for detecting a lithium battery capacity according to the application of the compensation calculation method described in claim 1, wherein the open circuit voltage method measures the open circuit voltage measured by the lithium battery under no load. The value of the open circuit voltage is the initial capacitance. A method for detecting a lithium battery capacity according to the application of the compensation calculation method described in claim 3, wherein when the lithium battery is discharged, M=previous_USOC/SOC, M is a slope, and previous_USOC is the current display current of the previous second. Capacity, SOC is the current actual capacity. A method for detecting a lithium battery capacity according to the application of the compensation calculation method described in claim 3, wherein when the lithium battery is charged, M=previous_USOC/SOC, M is a slope, and previous_USOC is the current display power of the previous second. Capacity, SOC is the current actual capacity. A method for detecting a lithium battery capacity according to the application of the compensation calculation method described in claim 3, wherein delta_SOC=(DC-previous_DC)/FCC, DC is the accumulated capacity that has been discharged, and previous_DC is released. The accumulated capacity is not until the previous second, and the FCC is the full charge capacity. The method for detecting a lithium battery capacity according to the application of the compensation calculation method of claim 1 or 6, wherein the full charge capacity includes the temperature factor, the current change factor, the reserved capacity (ReservedCap), and the advance Reserve capacity (PreReservedCap). The method for detecting a lithium battery capacity according to the application of the compensation calculation method described in claim 1, wherein the lithium battery capacity detecting method is performed by a controller, a microcontroller, a processor, and a micro processing One of the devices performs the operation.