JPH07191109A - Residual capacity detecting method for electric automobile battery - Google Patents

Abstract

PURPOSE:To detect the residual capacity of a battery under charge with high accuracy by finding an actual charge amount from an accumulated charged amount obtained by accumulating an average charge current for every preset time and a charge efficiency. CONSTITUTION:A current detector 16 detects a discharge current ID and a charge current Ic supplied from a charger 14. A voltage detector 18 detects voltage (battery voltage) E between the terminals of a battery 12 and a temperature detector 20 detects the temperature T of the battery 12. In accordance with the detection data output from the detectors 16, 18 and 20, an electronic control unit(ECU) Q2 computes the residual capacity of the battery 12. In a charge mode, a charge efficiency M is computed from the voltage E, and the charge efficiency M is multiplied by an accumulated charge amount Cc to set a charge amount enough for a rated capacity CF. In addition, a target charge amount is corrected by the battery temperature T so as to prohibit overcharge and short charge resulting from the change in the battery temperature T.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting a remaining capacity of a battery for an electric vehicle, and more particularly, it is possible to detect a remaining capacity of the battery during charging of a battery for driving a running motor of the electric vehicle. And a method for detecting the remaining capacity of a battery for an electric vehicle.

[0002]

2. Description of the Related Art Conventionally, in an electric vehicle, a secondary battery which can be charged and reused has been used as a drive source for a traveling motor and electric components.

In this battery for an electric vehicle, a so-called discharge state in which current is supplied to a traveling motor and electric components, a charge state in which a current is supplied from a charger, a discharge state, and a discharge state There is a state where the vehicle is not in any state of charge, that is, a state where the vehicle is left unattended.

Therefore, when detecting the remaining capacity in the state where the battery is charged, normally, the charging current amount at the time of charging is integrated every predetermined period to calculate an integrated charging amount, and this integrated charging amount is immediately before charging. The remaining capacity at the time of charging thus obtained is displayed by a remaining capacity indicator arranged on the front panel or the like of the electric vehicle.

[0005]

However, in the above-mentioned conventional method for calculating the remaining battery capacity during charging, the calculation result of the remaining capacity differs from the actual remaining capacity due to the detection error of the charging current. There is.

Further, since the remaining capacity of the battery being charged varies depending on the temperature of the battery being charged and deterioration due to aging, it is difficult to detect the remaining capacity of the battery with high accuracy. .

Furthermore, when the remaining capacity higher than the actual remaining capacity is displayed on the remaining capacity indicator, it causes the driver to misjudge the end time of charging.

The present invention has been made to solve such inconveniences of the prior art, and it is possible to detect the remaining capacity of the battery during charging with high accuracy and to substantially reduce the remaining capacity. It is an object of the present invention to provide a method for detecting a remaining capacity of a battery for an electric vehicle, in which there is no fear of displaying a remaining capacity higher than the capacity, and therefore, the determination of the charging end time is properly performed.

[0009]

In order to achieve the above-mentioned object, the present invention is a method for detecting the remaining capacity of a battery for driving a running motor for an electric vehicle during charging.
A first step of detecting the remaining capacity of the battery at the start of charging based on the voltage of the battery, and calculating a necessary charge amount from the remaining capacity of the battery at the start of charging and the previously stored rated capacity of the battery; A second step of detecting a temperature of the battery and obtaining a temperature correction coefficient for correcting the required charge amount by the battery temperature based on the battery temperature; and the required charge amount and the temperature correction coefficient, A third step of calculating a target charge amount at the battery temperature, and a charging efficiency indicating a ratio of the charging current converted into the remaining capacity in the charging current supplied to the battery to the battery voltage during charging. And a fifth step of obtaining an actual charge amount from the integrated charge amount obtained by integrating the average charge current for each predetermined time and the charge efficiency. Characterized in that it consists of.

Further, according to the present invention, when the actual charge amount reaches the target charge amount and the full charge flag indicates that the full charge is reached, a signal for stopping energization of the charging current is output. And the information indicating that the remaining capacity of the battery has reached the target charge amount when the change in the battery voltage for each predetermined period is within a set value or the change in the battery temperature for each predetermined period is equal to or more than the set value. Is set to the full charge flag.

[0011]

In the method for detecting the remaining capacity of the battery for the electric vehicle according to the present invention, in the battery being charged, the remaining capacity at the start of charging detected based on the battery voltage and the rated capacity of the battery are calculated. A target charge amount obtained by correcting the required charge amount based on the battery temperature is obtained.

On the other hand, the actual charge amount obtained by correcting the integrated charge amount with the charging efficiency is obtained, and when the actual charge amount reaches the target charge amount, a signal for stopping the energization of the charging current is output.

Therefore, it is possible to suppress an error that occurs when the remaining capacity is detected due to the battery temperature and the charging efficiency.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, a method for detecting the remaining capacity of a battery for an electric vehicle according to the present invention will be described in detail below with reference to the accompanying drawings, with reference to preferred embodiments in relation to an apparatus for carrying out the method. .

FIG. 1 is a block diagram showing the configuration of a battery remaining capacity detecting device 10 according to an embodiment of the present invention.

The battery remaining capacity detecting device 10 comprises a plurality of batteries 12 connected in series and a motor M _O driven by the battery 12, and the battery 12
A charger 14 for charging is connected at a desired time.

The battery remaining capacity detecting device 10 includes a current detector 16 for detecting a discharge current I _D supplied to the motor M _O and other electric components, and a charging current I _C supplied from the charger 14, and A voltage detector 18 for detecting a voltage E between terminals of the battery 12 (hereinafter referred to as a battery voltage) and a temperature detector 20 for detecting the temperature of the battery 12.
And a current detector 16 and a voltage detector 1
8 and an electronic control unit (hereinafter referred to as ECU) 22 that calculates the remaining capacity C of the battery 12 based on the respective detection data output from the temperature detector 20.

The battery remaining capacity detecting device 10 further comprises:
The charging target connector 24 has a charging target connector 24, and the charging target connector 24 can be attached to a charging connector 26 connected to the charger 14. In addition, the battery remaining capacity detection device 10 detects the connection detection sensor 28 that detects whether or not the charging connector 26 of the charger 14 is engaged with the charged connector 24, the ignition switch 30, and the accelerator operation angle of the accelerator. And an accelerator sensor 32 for detecting. The battery remaining capacity detection device 10 further includes a battery 12 and a motor M _O.
A switch 34 arranged between the connection with the motor and the motor M _O
It has a power drive unit (hereinafter referred to as PDU) 36 for driving the. Note that the ECU 22 uses the sub battery 3
It is driven by the power supply supplied from 8.

The ECU 22 determines the remaining capacity C of the battery 12.
A read-only memory (hereinafter, referred to as ROM) 42 in which a program for calculating is calculated, and a read / write free memory (hereinafter, referred to as RAM) that temporarily stores a calculation result when the ECU 22 calculates the remaining capacity C. 44 and EC
A lookup table (hereinafter referred to as LUT) 46 that is read when the U22 calculates the remaining capacity C is provided.

FIG. 2 shows the contents of the RAM 44.

The RAM 44 has a threshold value storage section 44a in which respective threshold values read when the data is judged by the ECU 22 are stored in advance, and a discharge current I read by the ECU 22 via the current detector 16. _The discharge current data storage unit 44b in which _D is temporarily stored, and the battery voltage E read by the ECU 22 via the voltage detector 18
Is temporarily stored in the battery voltage data storage section 44c.
When the number of times the threshold value E ₁ or less for storing the number of times that the detected battery voltage E through a voltage detector 18 becomes a threshold E ₁ below, which is stored in the threshold storage unit 44a in the discharge mode a storage unit 44d, and the uncorrected residual capacity storage unit 44e for storing the uncorrected residual capacity C _t, temperature compensation capacitor C for correcting the pre-correction before correction stored in the remaining capacity storage unit 44e residual capacity C _{t The} remaining capacity correction data storage unit 44f stores the calculated data of _{T 1} , the current correction capacity C _D , the deterioration correction capacity C _R, and the provisional correction capacity C _TM .

Further, the RAM 44 has a battery voltage E
Threshold E₁Discharge current I discharged when:
_DOf the smallest discharge current I_minTo remember
The small discharge current storage unit 44g and the temperature detector 20 are used for detection.
Battery temperature storage unit for storing the discharged battery temperature T
44h and the charging efficiency M calculated by the ECU 22
The charging efficiency storage unit 44i to store and the battery 12
The maximum output density obtained by dividing the maximum output that can be output by the battery weight.
The maximum output density storage unit 44j that stores the
Memorize the average maximum power density obtained by averaging the maximum power densities.
Average maximum output density storage unit 44k and remaining capacity C before correction_t
Remaining capacity C after correction with various correction values _rMemorize
The post-correction remaining capacity storage unit 44m is provided.

3 to 5 are graphs of data stored in the LUT 46.

The table T1 shown in FIG. 3A is based on the battery voltage E _BB per battery and the uncorrected remaining capacity C _{t of the} battery 12.
3B is a graph for reading out, the table T2 shown in FIG. 3B is a correction value for correcting the change in the remaining capacity C due to the temperature of the uncorrected remaining capacity C _t of the battery 12 from the battery temperature T detected by the temperature detector 20. 9 is a graph for reading (temperature correction capacitance C _T ).

A table T3 shown in FIG. 4A is a graph for reading a correction value (current correction capacity C _D ) for correcting the pre-correction remaining capacity C _t of the battery 12 from the average discharge current I _{DA for} one minute. The table T4 shown in FIG.
In the charging mode the charging current I _C is supplied to the battery 12, among the supplied charging current I _C, the ratio of the charging current I _C to be converted as uncorrected residual capacity C _t in the battery 12 (charging It is a graph for reading the efficiency M) from the battery voltage _EBB per piece.

Further, the table T5 shown in FIG. 5A is a graph for reading out the stable battery voltage E _BB predicted after a lapse of a predetermined time from the battery voltage E _BB per battery after 30 minutes of standing, and FIG. Table T6 shown in is a graph for reading the temperature correction coefficient X of the charging rate Y from the battery temperature T.

In the battery remaining capacity detection device 10 configured as described above, the corrected remaining capacity of the battery 12 in the discharge mode in which electric current is supplied from the battery 12 to the electric components such as the motor M _O and the air conditioner. A method of detecting C _r will be described with reference to the flowchart of FIG.

When the ignition key inserted in the ignition switch 30 is rotated by the driver to the starting position of the motor M _O , the ECU 22 determines the discharge mode by the signal output from the ignition switch 30 (step S10). Based on this determination, the switch 34 is switched by the signal output from the ECU 22, and the battery 12 and the PDU 36 are electrically connected. On the other hand, the drive signal of the motor M _O is output from the ECU 22 to the PDU 36, and the battery voltage E is applied to the motor M _O via the switch 34 and the PDU 36 by this drive signal, and the motor M _O is rotationally driven. It

When the motor M _O is rotationally driven, the battery voltage E detected by the voltage detector 18 has a predetermined sampling time, for example, one minute every 100 msec, that is, data of the battery voltage E of 600 is obtained by the ECU 22.
The discharge current _ID supplied from the battery 12 to the motor M _O detected by the battery voltage data storage unit 44c of the RAM 44 and detected by the current detector 16 is 1 minute every 100 msec, that is, , 600 of the discharge current I _D is read by the ECU 22 (step S12) and stored in the discharge current data storage unit 44b of the RAM 44.

Then, the average battery voltage E _A of the battery voltages E of 600 stored in the discharge current data storage section 44b of the RAM 44 is calculated by the ECU 22, and further the battery voltage E _BB per one is calculated. Based on this one battery voltage E _BB , the LUT 46
The initial value of the pre-correction remaining capacity C _t of the battery 12 in the discharge mode is read from the table T1 stored in the table T1 and stored in the pre-correction remaining capacity storage unit 44e (step S1).
4).

Further, of these 600 data, the first data stored in advance in the threshold value storage section 44a of the RAM 44 is used.
The number of times the battery voltage E becomes equal to or less than the threshold value E ₁ of E
The RAM 44 is counted by the CU 22 (step S16).
Together are stored in the threshold E ₁ below count storage section 44d of the discharge current I _D when the battery voltage E is was the first threshold value E ₁ or less are extracted, it was further said extracted The minimum discharge current I _min is extracted from the discharge current I _D and stored in the minimum discharge current storage unit 44g of the RAM 44 (step S18).

In this case, as shown in FIG. 7, the discharge current I
_The battery voltage E changes depending on the value of _D ,
The battery voltage E drops significantly due to the discharge current I _D that is smaller as the battery 12 deteriorates.

[0033] Then, the data of the discharge current I _D of the discharge current data storage unit 600 stored in 44b of RAM44 are read in step S2 is added read and the ECU 22, the summed discharge current I _D The average discharge current I _{DA for} 1 minute from is calculated (step S2
0), and the discharge amount ΔC for one minute is calculated from the average discharge current I _DA (step S22).

The discharge amount ΔC for one minute is the remaining capacity C before correction.
It is subtracted from the initial value of _t , and the uncorrected remaining capacity C _t stored in the uncorrected remaining capacity storage unit 44 e of the RAM 44 is updated by the subtracted uncorrected remaining capacity C _t (see the equation (1)) ( Step S24).

C _t ← C _t −ΔC (1) As described above, the pre-correction remaining capacity C _t is 1 by the ECU 22.
It is updated every minute, and the updated uncorrected remaining capacity C _t is R in advance.
It is determined whether or not it is equal to or less than the minimum remaining capacity C _min stored in the threshold value storage section 44a of the AM 44 (step S26). If it is less than or equal to the minimum remaining capacity C _min , the pre-correction remaining capacity storage section 44e.
The remaining uncorrected capacity C _t stored in is updated to the minimum remaining capacity C _min (step S28).

When the pre-correction remaining capacity C _t updated every minute is not less than or equal to the minimum remaining capacity C _min, it is determined whether it is greater than or equal to the maximum remaining capacity C _max stored in advance in the threshold storage unit 44a of the RAM 44. It is determined by the ECU 22 (step S3
0), if it is above, the uncorrected remaining capacity C _t stored in the uncorrected remaining capacity storage unit 44e is updated to the maximum remaining capacity C _max (step S32).

Next, the battery temperature T detected by the temperature detector 20 is read by the ECU 22, and based on the battery temperature T, the table T2 stored in the LUT 46 is used to correct the remaining capacity C _t of the battery 12 before correction. value (temperature compensation capacitance C _T) is stored in the read and the remaining capacity of the RAM44 correction data storage unit 44f (step S3
4).

Further, from the table T3 stored in the LUT 46 based on the average discharge current I _DA for 1 minute calculated in step S20, the correction value of the uncorrected remaining capacity C _t of the battery 12 at the average discharge current I _DA ( Current correction capacity C
_D ) is read and stored in the remaining capacity correction data storage unit 44f (step S36).

Next, a correction value for correcting the change in the rated capacity C _F due to the deterioration of the battery 12 (deterioration correction capacity C F
_R ), and the battery 1 based on the integrated value of the discharge amount ΔC
The correction value (provisional correction capacity C _TM ) for correcting the error of the remaining capacity C due to the accumulated error of the discharge amount ΔC that occurs when the remaining capacity C of 2 is calculated is calculated by the ECU 22 in a deterioration correction value calculation subroutine described later. And stored in the remaining capacity correction data storage section 44f of the RAM 44 (step S3).
8). The provisional correction capacity C _TM is
It also occurs when the charging current I _C is integrated and the pre-correction remaining capacity C _t is calculated.

The temperature correction capacity C _T , the current correction capacity C _D , the deterioration correction capacity C _R and the provisional correction capacity C _TM thus obtained are used to correct the remaining capacity C _t before correction through the ECU 22, and after the correction. The remaining capacity C _r is calculated (see equation (2)) (step S40).

C _r ← C _t + C _T + C _D −C _R −C _TM (2) Here, the deterioration correction value calculation subroutine of step S 38 will be described in detail below with reference to the flowcharts of FIGS. 8 to 12. .

The ECU 22 adds the data of 600 of the battery voltage E read every minute in the step S12 and stored in the battery voltage data storage section 44c of the RAM 44 to obtain the added battery voltage E _D (step S38). -2), the product of the discharge current I _D that is added by the adder battery voltage E _D and step S20 are calculated (E _D × I _D) (step S38-4), further summed discharge current I _D The squared value of is calculated (step S
38-6).

Next, is the number of times of the battery voltage E counted below the first threshold value E ₁ counted in step S16 above the set value S ₁ previously stored in the threshold value storage section 44a of the RAM 44? Whether or not it is determined by the ECU 22 (step S38-8), and when the set value is S ₁ or more, W
The AT1 flag is set to "1" (step S38-
10) Further, in the data of 600 of the battery voltage E read every minute in step S12, the RAM4 is previously stored.
Battery voltage E stored in the threshold storage unit 44a of No. 4
Second number of a threshold E ₂ or less, it is determined whether or not the set value S ₂ or more (step S38-12), the "1" WAT2 flag if set value S ₂ or more set of (Step S38-14).

The number of times the battery voltage E becomes equal to or less than the first threshold value E _{1 in} step S38-8 is the set value S ₁
If not, the determination in step S38-12 is executed without setting the WAT1 flag to "1",
Further, in step S38-12, the second threshold value E ₂
When the number of times the battery voltage E becomes equal to or less than the set value S ₂ is not equal to or more than the set value S ₂ , the calculation for obtaining the average maximum output density P _A is executed in step S38-18 without setting "1" to the WAT1 flag. To be done.

Next, a method of calculating the average maximum output density P _A in step S38-18 will be described.

The addition battery voltage E _D calculated in step S38-2, the product of the addition battery voltage E _D calculated in step S38-4 and the discharge current I _D added, and the addition calculated in step S38-6 Discharge current I _D
A linear expression showing the relationship between the added battery voltage E _D and the added discharge current I _D is obtained by the calculation of the least squares method using the squared value of the above, and the maximum output P _{max of the} battery 12 is calculated from this linear expression. Further, this maximum output P _max is divided by the weight of the battery 12 to calculate the maximum output density, which is stored in the maximum output density storage unit 44j of the RAM 44.

The maximum power density of the past N times, for example, five times including the maximum power density thus obtained is the ECU 22.
Is read from the maximum output density storage unit 44j, the average value of these is calculated to obtain the average maximum output density P _A (step S38-18), and stored in the average maximum output density storage unit 44k of the RAM 44.

[0048] sequentially accumulated has been accumulated discharge current amount C _M discharge amount ΔC of 1 minute, which is calculated in the step S22 is the ECU22 is calculated (step S38-20), further, uncorrected RAM44 determined in step S14 remaining capacity storage unit 44e on the stored uncorrected residual capacity C _t the accumulated discharge current amount C _M is subtracted by uncorrected residual capacity C _t from the initial value of is determined (step S38-22), the uncorrected residual The capacity C _t is the uncorrected remaining capacity storage section 44 e of the RAM 44.
Memorized in.

Next, it is judged whether or not the average maximum output density P _A has been obtained (step S38-24). If so, this average maximum output density P _A is previously stored in the RAM.
The ECU 22 determines whether or not the threshold value K is less than or equal to the threshold value K stored in the threshold value storage unit 44a (step S).
38-26). This threshold value K is for determining whether or not the actual remaining capacity C of the battery 12 is "0". Therefore, if it is determined in step S38-26 that the threshold value K is less than or equal to the threshold value K, It is determined that the remaining capacity C of 12 is substantially "0" or less (step S38-2).
8).

[0050] Then, the temperature correction capacitor C _T the computed uncorrected residual capacity C _t in step S38-22, the current correction capacitor C _D, degradation corrective capacity C _R and the provisional correction capacitor C _TM in corrected corrected residual capacity EC whether C _r is less than “0”
It is determined by U22 (see the equation (3)) (step S38-30).

C _t + C _T + C _D −C _R −C _TM ≦ 0 (3) It should be noted that the deterioration correction capacity C _R and the provisional correction capacity C _TM used in the calculation of the equation (3) are the remaining capacity correction data of the RAM 44. This is the previous value stored in the storage unit 44f.

As a result of the determination in step S38-30,
If it is determined that it is not "0" or less, the corrected remaining capacity C _r
Is determined to be "0" or more (step S3).
8-32). In this case, in step S38-28, the actual remaining capacity C is calculated based on the average maximum output density P _A.
Despite being determined to be "0" or less, it is determined that the post-correction remaining capacity C _r obtained based on the integration of the discharge amount ΔC is "0" or more.

Then, the difference between the average maximum output density P _A and the threshold value K is calculated by the ECU 22 (step S3).
8-34), a predetermined value, for example, a value obtained by dividing by 10 is used as the deterioration amount calculation coefficient S _A (step S38-
36), it is determined whether or not the deterioration amount calculation coefficient S _A is 1 or more (steps S38-38).

As a result of this determination, the deterioration amount calculation coefficient S _A is 1
If the average maximum output density P _A is significantly lower than the threshold value K, the deterioration amount calculation coefficient S _A is set to the maximum value 1 by the ECU 22 (step S
38-40), the content of the leaving flag set in the leaving mode described later is read out, and it is determined whether or not the content of the leaving flag is "1" (step S38-4).
2).

If the content of the leaving flag is "1", EC
U22 is for calculating the discharge amount ΔC in the discharge mode.
Discharge current I_DThe integration error caused by the integration of
It is determined that the cells have been cellized (steps S38-44), and the discharge amount
Corrected remaining capacity C obtained based on the integration of ΔC_rBack to
It is judged that the error due to the deterioration of the terry 12 is included.
(Step S38-46), based on the following equation (4)
A deterioration correction capacity C of the battery 12 is calculated._RTo calculate
(Step S38-48), this deterioration correction capacity C _RBy
Stored in the remaining capacity correction data storage section 44f of the RAM 44.
The previous deterioration correction capacity C_RUpdate to Mainle
To return to China.

C _R ← C _R + (C _J + C _T + C _D −C _R −C _TM ) × S _A (4) In step S38-38, the deterioration amount calculation coefficient S
_{If A} is not 1 or more, the value obtained by the calculation in step S38-36 is set as the deterioration amount calculation coefficient S _A (step S38-50), and steps S38-42 and subsequent steps are executed.

If it is determined in step S38-42 that the leaving flag is not "1", the ECU 22 has not canceled the integration error caused by the integration of the discharge amount ΔC, that is, the error due to the provisional correction capacity C _TM is corrected. It is determined that it is included in the remaining capacity C _r (step S38-
52), this temporary correction capacity C _TM is calculated by the following equation (5) (step S38-54), and the remaining capacity correction data storage unit 44 of the RAM 44 is calculated by this temporary correction capacity C _TM .
The previous temporary correction capacity C _TM stored in f is updated, and the process returns to the main routine.

C _TM ← C _TM + (C _J + C _T + C _D −C _R −C _TM ) × S _A (5) Thus, the maximum average power density P _A is lower than the threshold value K, that is, When the post-correction remaining capacity C _r is equal to or greater than “0”, even though the actual remaining capacity C is equal to or less than “0”,
Whether the error contained in the post-correction remaining capacity C _r is due to the deterioration correction capacity C _R or the temporary correction capacity C _TM is determined by determining whether the content of the leaving flag is “1”. The value of the deterioration correction capacity C _R or the provisional correction capacity C _TM is calculated and updated based on the determination result.

In this case, the leaving flag is set in the leaving mode described later, and when the leaving flag is set to "1", the accumulated error up to that point is canceled.

On the other hand, when it is determined that the determination result of the equation (3) in step S38-30 is smaller than "0", the actual remaining capacity C is "0" or less and the corrected remaining capacity C is equal to or less than "0". _{Since r} is equal to or less than “0”, the ECU 22 determines that the corrected remaining capacity C _r and the deterioration correction capacity C _R and the temporary correction capacity C
_It is judged that the error due to _TM is not included (step S
38-56), and returns to the main routine.

When it is determined in step S38-26 that the average maximum output density P _A is not smaller than the threshold value K, the determination of the equation (3) is made by the ECU 22 (step S38-58). When it is determined that the determination result is not smaller than "0", it is determined whether the WAT2 flag is "1" (step S38-6).
0), when it is not "1", it is determined whether or not the WAT1 flag is "1" (step S38-62). When the result of this determination is not "1", the actual remaining capacity C is "0". "
The corrected remaining capacity C _r obtained based on the integration of the discharge amount ΔC is determined to be “0” or more, and is obtained based on the integration of the actual remaining capacity C and the discharge amount ΔC. It is determined that the corrected remaining capacity C _r is the same as the corrected remaining capacity C _r, and it is determined that the remaining capacity C is sufficiently present and is in a normal state, and the process returns to the main routine.

If the WAT1 flag is "1" in the determination of step S38-62, the ECU 22 determines whether the minimum discharge current I _min extracted in step S18 is less than or equal to the threshold value K1 for determining the decrease of the remaining capacity C. It is determined whether or not (step S38-64), and when it is not less than or equal to this threshold value K1,
The battery 12 is determined to be in a normal state where it has not reached the end of its life due to deterioration, and the process returns to the main routine.

Minimum discharge current I_minIs below the threshold K1
When there is, the remaining capacity determination flag for determining the presence or absence of the remaining capacity C
Is set to "1" (step S38-66), and
And the deterioration amount calculation coefficient S_AIs set to the maximum of 1 (
Steps S38-68), the steps S38-42 and thereafter.
At the deterioration correction capacity C_ROr provisional correction capacity C _TM
Is executed.

When the WAT2 flag is "1" in the determination in step S38-60, it is determined that the remaining capacity C is insufficient, and in step S38-66 and thereafter, the deterioration correction capacity C _R or the temporary correction capacity C _TM is determined. The operation is executed.

If the average maximum output density P _A is not found in step S38-24, the ECU
When the determination is made according to step 22, the determination of the formula (3) is executed (steps S38-70), and the result of this determination is
When it is not equal to or less than "0", the average maximum output density P _A has not been obtained, but it is determined that the remaining capacity C is sufficient, and the steps S38-60 and thereafter are executed.

On the other hand, in steps S38-58 and before.
Note that the determination by the equation (3) in step S38-70
When the result is "0" or less, the temperature correction capacity C_T, Current
Correction capacity C_D, Deterioration correction capacity C_RAnd provisional correction capacity C
_TMRemaining capacity C after correction corrected by_rIs judged to be "0" or less
Then, it is determined whether or not the WAT2 flag is "1" (step
S38-72), if not "1", WAT1 flag
It is determined whether the flag is "1" (step S38-7).
4) If this judgment result is not "1", the remaining capacity judgment flow
It is determined whether or not the lag is "1" (step S38-7).
6) If not "1", the average maximum power density P_AWanted
Is determined (step S38-78),
If found, the compensation obtained based on the integration of the discharge amount ΔC
Positive remaining capacity C_rIs "0" or less, but the actual remaining capacity
It is determined that C is "0" or more, and the step S38-3 is performed.
6 and later are executed and the deterioration correction capacity C_R, Or provisional supplement
Positive capacity C _TMIs calculated.

In this case, as shown in FIG. 13, the rated capacity C _F of the battery 12 has a characteristic that it temporarily increases as the number of charging cycles increases and then decreases after reaching a predetermined number of charging cycles, so deterioration correction is performed. The capacity C _R can take either a positive or negative value with respect to the rated capacity C _F.

If it is determined in step S38-76 that the remaining capacity determination flag is "1", and if it is determined in step S38-78 that the average maximum output density P _A has not been determined, the main routine is executed. To return.

In steps 38-74 above, the WAT
When the 1 flag is “1”, the ECU 22 determines in step S
It is determined whether or not the minimum discharge current I _min extracted in 4 is less than or equal to the threshold value K1 for determining the decrease of the remaining capacity C (step S38-80), and when it is not less than or equal to the threshold value K1,
When the steps 38-76 and thereafter are executed and the threshold value K1 or less, the remaining capacity C is determined to be "0" or less and the remaining capacity determination flag is set to "1" (step S3).
8-82) and returns to the main routine.

In step S38-72, WA
When the T2 flag is determined to be "1", the ECU 22 determines that the remaining capacity C is equal to or less than "0", and the step S38-
At 82, the remaining capacity determination flag is set to "1", and the process returns to the main routine.

[0071] As described above, in the discharge mode, uncorrected residual capacity C _t of the pre-correction battery 12 the initial value of the residual capacity C _t and from the integrated value of the discharge amount ΔC of 1 minute per minute is calculated , The remaining capacity before correction C _t is the temperature correction capacity C _T , the current correction capacity C _D , the deterioration correction capacity C _R, and the provisional correction capacity C
_The corrected remaining capacity C _r can be obtained with high accuracy by being corrected by _TM .

Further, the calculated average maximum output density P _A
Is equal to or less than the threshold value K indicating "0" of the substantial remaining capacity C, it is determined whether the corrected remaining capacity C _r obtained based on the integration of the discharge current _ID is equal to or less than "0". If it is determined that the corrected remaining capacity C _r is “0” or more, the cause of the error between the actual remaining capacity C and the corrected remaining capacity C _r is the deterioration correction capacity C _R based on the content of the leaving flag. those to or by determining whether by temporary corrective capacity C _TM, calculates a degradation corrective capacity C _R or temporary corrective capacity C _TM, by calculating the corrected residual capacity C _r on the basis of these values, high The remaining capacity C _r after accuracy correction can be obtained.

Next, a detection method for detecting the remaining capacity C of the battery 12 in the charging mode will be described with reference to the flow charts of FIGS. 14 and 15.

The charging method of the battery 12 in this embodiment is a constant current method and the first current value I ₁
After a predetermined period of time, the two-stage charging method of charging with the second current value I ₂ lower than the first current value I ₁ is used, FIG. 16A shows the charging current waveform, and FIG. 16B shows 16B shows a waveform of the battery voltage E when the battery 12 is charged with the charging current waveform shown in 16A.

Charging connector 26 connected to charger 14
Is connected to a charged connector 24 arranged in the electric vehicle, and when a connector connection signal is output from the connection detection sensor 28 arranged in the charged connector 24 to the ECU 22, the ECU 22 determines the charging mode. (Step S100), the charging mode determination flag is set to "1".
Is set, and the leaving mode determination flag is set to "0" (step S102). Further, the ECU 2
The switch 34 is switched by the signal output from the terminal 2, and the connection between the battery 12 and the motor M _O is cut off.

Next, when the charging current I _C is started to be supplied from the charger 14 to the battery 12 (step S1).
04), the charging current I detected by the current detector 16
The data of _C is output to the ECU 22, and the data of the battery voltage E detected by the voltage detector 18 is output to the ECU 22.

The charging current I _C and the battery voltage E are set to 1 at a predetermined sampling time, for example, every 100 msec.
Minutes, that is, data of 600 is read by the ECU 22 and stored in the charging current data storage unit 44b and the battery voltage data storage unit 44c, and the average charging current I _{CA for} 1 minute and the average value of the battery voltage E for 1 minute. Is calculated (step S106), and the battery voltage E _BB per battery is calculated (step S10).
7).

Next, the ECU 22 determines whether or not the full charge flag is set to "1", that is, whether or not the battery 12 is in the fully charged state (step S1).
08). If it is determined that the battery is fully charged, the charger 1
It is determined that the charging current I _C supplied from No. 4 is converted into heat without being converted as the remaining capacity C,
Among supplied by which the charging current I _C, the ratio of the charging current I _C to be converted in the battery 12 as the remaining capacity C, that the charging efficiency M is determined to zero percent, the charging efficiency storage unit of this value is RAM44 It is stored in 44i (step S110).

On the other hand, when the full charge flag is not set to "1", the ECU 22 determines that the charging is insufficient, and further, the charging current I supplied from the battery 12 is determined.
_It is determined whether _C is the first current value I ₁ (step S
112). If the result of this determination is the first current value I _1, it is assumed that all of the supplied charging current I _C has been converted into the remaining capacity C in the battery 12, and the charging efficiency M is 10
It is determined to be 0%, and this value is stored in the charging efficiency storage unit 44i of the RAM 44 (step S114).

When it is determined in step S112 that the current value is not the _first current value I ₁ , the ECU 22 determines the second current value I 1.
₂ is determined to be energized (step S11
5) The charging efficiency M is read from the table T4 stored in the LUT 46 based on the battery voltage E _BB per battery calculated in step S107, and this value is stored in the RAM.
It is stored in the charging efficiency storage unit 44i of 44 (step S
116).

In this case, steps S108 to S
The charging efficiency M, which is either 0%, 100%, or the value of the charging efficiency M read from the table T4, is calculated by the charging efficiency storage unit 44i of the RAM 44.
Memorized in.

Next, the battery temperature T is read by the ECU 22 via the temperature detector 20, and the table T2 stored in the LUT 46 based on the battery temperature T is read.
The temperature correction capacitance C _T is read from and stored in the RAM 44 (step S118).

Further, the ECU 2 is connected via the temperature detector 20.
Table T based on the battery temperature T read in 2
6, the temperature correction coefficient X of the charging rate Y is read (step S120), and the temperature correction coefficient X is multiplied by a predetermined margin rate, for example, 115% to calculate the charging rate Y (Y = X × 1). .15) (step S122). Here, the charging rate Y is the rated capacity C _F and the current post-correction remaining capacity C _r.
And the target charge amount.

Next, from the rated capacity C _{F of} the battery 12, the initial value of the pre-correction remaining capacity C _t of the battery 12 previously obtained at the start of charging is subtracted to obtain the target charge amount. The target charging amount is calculated by multiplying the temperature-corrected charging rate Y (see equation (6)) (step S124).

Target charge amount = (C _F −C _CF ) × Y (6) In this case, since the charging rate Y is multiplied by 115% in step S122, the target charge amount is the rated capacity C _F.
Set to a value 15% higher.

Then, the ECU 22 executes step S1.
06 charge amount [Delta] C _C for one minute from the calculated average charging current I _CA is calculated, the accumulated charge amount C _C is calculated charged amount [Delta] C _C of 1 minute is accumulated (step S12
6).

Further, the ECU 22 determines whether or not the integrated charge amount C _C is equal to or more than the target charge amount (step S12).
8) If the result of this determination is that the integrated charge amount C _C > the target charge amount, the ECU 22 determines whether or not the full charge flag is set to "1" (step S12).
9) If "1" is not set, the current post-correction remaining capacity C _r is calculated as follows.

[0088] The calculation method of the corrected residual capacity C _r, said the integrated charge amount C _C that is accumulated from the start of charging step S1
10, the charging efficiency M stored in the RAM 44 is multiplied by S114 or S116, and the charging amount (C _C × M) is calculated by the ECU.
Determined by 22, the charging amount (C _C × M) and the current from the initial value of the uncorrected residual capacity C _t uncorrected residual capacity C _t is calculated (see (7) expression) (step S130).

C _t ← C _t + C _C × M (7) Next, the temperature correction capacity C _T read in step S118 and the remaining capacity correction data storage unit 44f of the RAM 44 calculated in the above-described charging mode. The post-correction remaining capacity C _r obtained by correcting the pre-correction remaining capacity C _t is calculated using the stored deterioration correction capacity C _R and provisional correction capacity C _TM (see equation (8)).
(Step S132).

C _r ← C _t −C _T −C _R −C _TM (8) On the other hand, in the determination of step S128, the integrated charge amount C
_{When C 1} > the target charge amount, it is determined that the integrated charge amount C _C has reached the target charge amount, it is determined that the charge has been sufficiently performed, and the charger 1 is output by the signal output from the ECU 22.
The supply of the charging current I _C to the battery 12 from 4 is stopped (step S134), and the charging mode ends.

As a result of the determination in step S129,
If "1" is set, it is determined that the integrated charge amount C _C has reached the target charge amount, and the energization stop in step S134 is executed.

The full-charge flag used to determine whether or not to end this charging mode is a predetermined period, for example, 30
It is set according to the determination result of the full charge determination subroutine executed every minute.

Next, the full charge determination subroutine will be described below.

The current charging current I _Cn is read by the ECU 22, and it is determined whether or not the difference between this charging current I _Cn and 30 minutes before, that is, the previous charging current I _Cn-1 is within 1 ampere (step). S138) If it is within 1 amp, the charging current I _C is changed from the first current value I ₁ to the second current during the 30 minutes.
It is determined that the current value I ₂ has not changed.

Then, the ECU 22 determines whether or not the current charging current I _Cn is a set value, for example, 10 amperes or less (step S139).
Current value I ₂ of is determined to be energized (step S
140), there are more, the difference between the set value of the battery voltage E _n-1 of the current battery voltage E _n and the previous measurement, for example, it is determined whether or not less than one volt (step S141), in less than one volt If it is determined that the battery is fully charged, the full-charge flag is set to "1" (step S142), the process is repeated from step S100, and step S128
When it is determined that the full charge flag is set to "1" in, the charging mode ends.

On the other hand, when it is determined in step S141 that the voltage is not less than 1 volt, it is determined that the battery voltage E is rising because the battery is not fully charged.
The current battery temperature T _n and the previously measured battery temperature T stored in the battery temperature storage unit 44 h of the RAM 44.
_It is determined whether or not the difference from _n-1 is a set value, for example, 1 ° C or higher (step S144), and if 1 ° C or higher, it is determined that the battery is fully charged and the full-charge flag is set to "1" in step S142. To be done.

That is, when the state of charge of the battery 12 reaches full charge, the rate of increase of the battery voltage E decreases (see FIG. 16B (a)), and the rate at which the charging current I _C is converted into heat is high. Therefore, the battery temperature T rises.
Therefore, during the period in which the second current value I ₂ is applied,
When the change in the battery voltage E is within 1 volt or the change in the battery temperature T is 1 ° C. or more, it is determined that the battery is fully charged.

[0098] On the other hand, when the difference between the charging current I _Cn-1 of the detected current charge current I _Cn and stored is previously measured in RAM44 in step S138 is not less than one ampere and charging in step S139 When the ECU 22 determines that the current I _C is not within 10 amperes, it is determined to be the period during which the first current value I ₁ is energized (step S146), and steps S141 and thereafter are executed. Further, the current battery voltage E _n and the previously measured battery voltage E _n are determined by the determination in step S141.
The difference from _n-1 is not less than 1 volt, and step S1
When the difference between the current battery temperature T _n and the battery temperature T of the previous measurement stored in the battery temperature storage unit 44 h of the RAM 44 is not 1 ° C. or more in the determination of 44, it is determined that the battery is not fully charged and the battery is fully charged. The flag is set to "0" (step S148), and the process is repeated from step S100.

As described above, in charging mode,
The charging efficiency M is calculated from the change in battery voltage E, and this charging is performed.
Efficiency M is accumulated charge C_CBy multiplying the
Quantity C _FIt is possible to set a sufficient charge amount.

Furthermore, by correcting the target charge amount based on the battery temperature T, it becomes possible to prevent overcharging and insufficient charging due to changes in the battery temperature T.

Next, a method of detecting the remaining capacity C of the battery 12 in the leaving mode will be described with reference to FIGS. 17 and 18.
This will be described with reference to the flowchart in FIG.

When the ignition key is removed from the ignition switch 30 by the driver to end the discharge mode, or when the charging connector 26 is removed to end the charge mode, the ECU 22 determines that the mode is the neglect mode (step S200). The battery voltage E when the mode is determined is read as the initial battery voltage E _{B1 in the} neglect mode (step S202).

[0103] Next, the time after the judgment of the leaving mode is made.
The ECU 22 determines whether or not the time t has reached 15 minutes.
If it is judged (step S204) and 15 minutes have passed,
Battery voltage E_B2Or E_B3Is read (step S2
06), this battery voltage E _B2Or E_B3Is the initial battery
Revoltage E_B1It is determined whether or not the voltage has increased by 0.1 volt or more from
(Step S208)
If not, it is EC that the previous mode was the charging mode.
Judgment by U22 (step S210), immediately before mode
"1" is set to the flag (step S212).

On the other hand, when the battery voltage E _B2 or E _B3 rises from the initial battery voltage E _B1 by 0.1 V or more, the ECU 22 determines that the immediately previous mode was the discharge mode (step S214), and the immediately previous mode is performed. "0" is set in the flag (step S216).

In this case, as shown in FIG. 19, the battery voltage E tends to decrease after the end of the charging mode and stabilize after the elapse of the predetermined time t _x , while the battery voltage E after the end of the discharging mode ends the discharging. Since there is a tendency to increase immediately after that, the immediately preceding mode is determined by whether or not the battery voltage E _B2 or E _B3 after 15 minutes has increased from the initial battery voltage E _B1 .

Then, the ECU 22 determines whether or not the elapsed time t from the determination of the neglect mode has reached 30 minutes (step S218). If 30 minutes has elapsed, the immediately preceding mode flag is "1". It is determined whether or not, that is, whether or not immediately before is the charging mode (step S220), and when immediately before is in the charging mode, the battery voltage E _{B2 at} this time is read via the voltage detector 18, and further, The battery voltage E _BB per battery at this time is calculated (step S222).

[0107] Battery voltage E _BB per one predicted to stabilize after a predetermined time t _x has elapsed based on the battery voltage E _BB of the 1 per from table T5 ECU 22
(Step S224), the pre-correction remaining capacity C _{t of the} battery 12 is read from the table T1 based on the predicted stable battery voltage E _BB, and the remaining capacity correction data storage unit of the RAM 44 is read. It is stored in 44f (step S226).

On the other hand, if it is determined in step S218 that the elapsed time t is not 30 minutes, it is determined whether the elapsed time t is less than 30 minutes (step S228). If it exceeds 30 minutes, the elapsed time t is 180 minutes. Is determined (step S232), and when it is not more than 180 minutes, that is, when the elapsed time t is more than 30 minutes and less than 180 minutes, the content of the immediately previous mode flag is read by the ECU 22. Then, it is determined whether or not immediately before is the charging mode (step S
234), when the content of the immediately preceding mode flag is "1", that is, in the charging mode, step S224 and the subsequent steps are executed, and the pre-correction remaining capacity C of the battery 12 is calculated based on the predicted stable battery voltage E _{BB. t} is read from the table T1 and the remaining capacity correction data storage unit 4 of the RAM 44 is read.
It is stored in 4f.

In this case, the uncorrected remaining capacity C _t is determined by the table T
By being read out from the 1, without obtaining the uncorrected residual capacity C _t based on the battery voltage E in after charging descend, the uncorrected residual capacity C _t based on the battery voltage E _BB predicted stable during For example, the shortage of the charge amount when the battery is charged immediately after this is prevented.

On the other hand, when it is determined in step S232 that the time exceeds 180 minutes, and when the determination in step S234 is that the content of the immediately preceding mode flag is not "1", that is, when the charging mode is not set, the battery is charged every predetermined sampling time. The voltage E is read (step S235), and the pre-correction remaining capacity C of the battery 12 at this battery voltage E is read.
_t is read from the table T1 stored in the LUT 46 in step S226. This remaining capacity C before correction
_The immediately before-correction remaining capacity C _t stored in the RAM 44 is updated by _t .

When the pre-correction remaining capacity C _t is read from the table T1, the leaving flag is set to "1" (step S236). This leaving flag “1” is the uncorrected remaining capacity C _t calculated in the charging mode, or
Of the uncorrected remaining capacity C _t calculated in the discharge mode,
This indicates that the integration error of the uncorrected remaining capacity C _t due to the integration of the charge amount ΔC _C or the integration of the discharge amount ΔC has been canceled.

That is, the correction is made by integrating the discharge amount ΔC.
Front remaining capacity C_tDischarge current I_D1 minute flat
Equal discharge current I_DAThe average discharge current I_DATo
There is an error in the calculation, and this error is accumulated.
Calculated remaining capacity C before correction _tAccumulation error occurs.
On the other hand, the uncorrected remaining capacity C read from the table T1 _t
Before correction including the accumulated error of the discharge amount ΔC
Capacity C_tWhen the is updated, the remaining capacity C before correction_tAccumulation of
The difference will be cancelled.

When it is determined in step S228 that the time is less than 30 minutes, the temperature correction capacity c _T is calculated in step S237 described later.

On the other hand, when the elapsed time t is a period of less than 30 minutes, a period of more than 180 minutes, a period of more than 30 minutes and less than 180 minutes, and immediately before is not the charging mode, the predetermined sampling time is set. The battery voltage E _BB per unit is calculated from the battery voltage E detected for each
The uncorrected remaining capacity C _t based on the battery voltage E _BB for each battery is read from the table T1.

When the immediately previous mode flag is not "1" in the determination at step S220, the ECU 22 determines that the immediately previous mode is the discharge mode, and step S228 and subsequent steps are executed.

Next, the battery temperature T is read by the ECU 22 via the temperature detector 20, and the battery temperature T
The temperature correction capacity C _T is read from the table T2 stored in the LUT 46 based on the above (step S237), and this temperature correction capacity C _T and the remaining capacity correction data storage unit 44f of the RAM 44 calculated in the above charging mode are calculated. The post-correction remaining capacity C _r obtained by correcting the pre-correction remaining capacity C _t is calculated by the deterioration correction capacity C _R and the provisional correction capacity C _TM stored in (C _r ← C _t −C _T −C _R −C _TM ) (Step S2
38).

Further, until the ECU 22 determines the discharge mode (step S240) or the charge mode (step S242), the step S is performed.
After step 202, the corrected remaining capacity C _r is repeatedly executed.
Is calculated.

As described above, in the leaving mode, the direct
Detected battery voltage when previously in discharge mode
Remaining capacity C before correction using E_tOn the other hand, just before is charged
Expected battery voltage after stabilization when in mode
E_BBDepending on the remaining capacity C before correction _tBy asking for
A battery that temporarily rises if it was in charge mode before
Remaining capacity C before correction based on voltage E_tIs calculated
Since there is no_tFrom the actual remaining capacity C
It is possible to prevent high calculation.

As described above, in the charging mode in this embodiment, the temperature correction coefficient X has a predetermined constant, for example,
Since the target charge amount is calculated by multiplying the difference between the rated capacity C _F and the pre-correction remaining capacity C _t by the charging rate Y multiplied by 1.15, the target charge amount becomes the rated capacity C _F or more, Therefore,
When the amount of charge reaches the target amount of charge and the charging is stopped, the corrected remaining capacity C _r of the battery 12 becomes equal to or higher than the rated capacity C _F, and it is possible to prevent the situation of insufficient charging.

[0120]

In the method for detecting the remaining capacity of the battery for the electric vehicle according to the present invention, it is possible to suppress the occurrence of the remaining capacity detection error due to the battery temperature and the charging efficiency in the battery being charged. The remaining capacity of the battery can be calculated as accurately as possible. further,
The driver will not be misjudged when determining when to end charging.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a battery remaining capacity detection device for carrying out an electric vehicle battery remaining capacity detection method according to the present invention.

FIG. 2 is a diagram illustrating each storage unit arranged in a RAM in the embodiment of FIG.

FIG. 3A is a graph illustrating the contents of a table showing the relationship between the battery voltage per battery and the remaining battery capacity stored in the LUT in the embodiment of FIG.
B is a graph illustrating the contents of a table showing the relationship between the battery temperature and the temperature correction capacity stored in the LUT in the embodiment of FIG.

4A is a graph for explaining the contents of a table showing the relationship between the average discharge current for 1 minute and the current correction capacity stored in the LUT in the embodiment of FIG. 1, and FIG. 4B is the embodiment of FIG. It is a graph explaining the content of the table which shows the relationship between the battery voltage per one and the charging efficiency stored in the LUT in the example.

FIG. 5A is a table showing the relationship between the battery voltage per unit stored in the LUT in the embodiment of FIG. 1 after 30 minutes of standing and the battery voltage per unit predicted when stable. FIG. 5B is a graph for explaining FIG.
6 is a graph illustrating the contents of a table showing the relationship between the battery temperature and the temperature correction coefficient stored in the LUT in the example of FIG.

FIG. 6 is a main flowchart illustrating a method of detecting a remaining capacity of a battery in a discharge mode according to an embodiment of the present invention.

FIG. 7 is a diagram illustrating a relationship between a discharging current and a battery voltage during discharging in a discharging mode according to an embodiment of the present invention.

FIG. 8 is a flowchart illustrating a deterioration correction value calculation subroutine in the main flowchart of the discharge mode shown in FIG.

9 is a flowchart illustrating a deterioration correction value calculation subroutine in the main flowchart of the discharge mode shown in FIG.

10 is a flowchart illustrating a deterioration correction value calculation subroutine in the main flowchart of the discharge mode shown in FIG.

FIG. 11 is a flowchart illustrating a deterioration correction value calculation subroutine in the main flowchart of the discharge mode shown in FIG.

12 is a flowchart illustrating a deterioration correction value calculation subroutine in the main flowchart of the discharge mode shown in FIG.

13 is a graph illustrating changes in rated capacity with respect to the number of charge / discharge cycles of the battery used in the example of FIG.

FIG. 14 is a flowchart illustrating a method for detecting a remaining capacity of a battery in a charging mode according to an embodiment of the present invention.

FIG. 15 is a flowchart illustrating a method for detecting a remaining capacity of a battery in a charging mode according to an embodiment of the present invention.

16A is a graph illustrating a waveform of a charging current supplied from a charger to a battery, and FIG.
16B is a graph illustrating a change in battery voltage when the battery is charged with the charging current shown in FIG. 16A.

FIG. 17 is a flowchart illustrating a method for detecting a remaining capacity of a battery in a leaving mode according to an embodiment of the present invention.

FIG. 18 is a flow chart illustrating a method for detecting the remaining capacity of a battery in a leaving mode according to the embodiment of the present invention.

FIG. 19 is a graph illustrating a change in the battery voltage with respect to the elapsed time in the neglect mode in the embodiment according to the present invention.

[Explanation of symbols]

10 ... Battery remaining capacity detection device 12 ... Battery 14 ... Charger 16 ... Current detector 18 ... Voltage detector 20 ... Temperature detector 22 ... ECU 24 ... Charged connector 26 ... Charging connector 28 ... Connection detection sensor 34 ... Switching device _{44 ... RAM 46 ... LUT M O} ... motor

Claims (3)

[Claims] 1. A method for detecting a remaining capacity of a battery for driving a traveling motor for an electric vehicle during charging, the remaining capacity of the battery at the start of charging being detected based on the voltage of the battery, A first step of calculating a required charge amount from a battery remaining capacity at the start of charging and a previously stored rated capacity of the battery; a temperature of the battery is detected; and the required charge amount is calculated based on the battery temperature. A second step of obtaining a temperature correction coefficient for correction according to the battery temperature; a third step of calculating a target charge amount at the battery temperature from the required charging amount and the temperature correction coefficient; A fourth step of obtaining, based on the battery voltage during charging, a charging efficiency indicating a ratio of the charging current converted into the remaining capacity in the charging current to be charged; A fifth step of obtaining an actual charge amount from the integrated charge amount obtained by integrating the average charge current for each predetermined time and the charging efficiency, and a remaining capacity detection method for an electric vehicle battery. 2. The method according to claim 1, wherein when the actual charge amount reaches the target charge amount and the full charge flag indicates that the full charge is reached, a signal for stopping the energization of the charging current is sent. A sixth step of outputting, and a method for detecting the remaining capacity of a battery for an electric vehicle, comprising: 3. The method according to claim 2, wherein when the change of the battery voltage in each predetermined period is within a set value or the change of the battery temperature in each predetermined period is equal to or more than the set value, the remaining capacity of the battery is a target. A method for detecting a remaining capacity of a battery for an electric vehicle, comprising the step of setting information indicating that the amount of charge has been reached in a full charge flag.