CN106353687A - Assessment method of lithium battery health status - Google Patents

Abstract

The invention provides a assessment method of lithium battery health status, the method including: confirming the assessment factor of lithium battery health status, computing initial value of assessment factor weight value for the lithium battery health status and actual value of assessment factor weight value for the lithium battery health status, assessing the health status of lithium battery. This invention synthesizes the terminal voltage change rate, ohmic internal resistance and polarize internal resistance of lithium battery as the assessment factors which improving the assessment accuracy of lithium battery health status, using the method of measuring and computing terminal voltage change rate, ohmic internal resistance and polarize internal resistance of lithium battery after the pulse finishing discharging at the same time, so as to ensure the state identity and time consistency of lithium battery state measurement and improve the assessment factor accuracy of lithium battery health status, synthesizing the effect of standard deviation and average number indicators of assessment factor, and reflecting better overall sign changes of assessment factor in different levels, realizing the fast and precise measuring for lithium battery health status.

Description

A kind of appraisal procedure of lithium battery health status

Technical field

The present invention relates to a kind of appraisal procedure is and in particular to a kind of appraisal procedure of lithium battery health status.

Background technology

The soh of lithium battery reflects security performance and the capacity attenuation degree of lithium battery group, and main characterising parameter has total appearance Change of the decay of amount and lithium battery internal resistance etc.；Lose because unexpected lithium battery health often leads to lithium battery system allomeric function Lithium battery health status are carried out estimation and the prediction of science by effect from the angle of application, instruct lithium battery to run further and tie up Shield, builds the status monitoring of lithium battery and health management system arranged, prevents lithium battery from overcharging, crosses and put, estimate lithium battery performance state With prediction lithium battery state evolution, it is the important parameter realizing the long-time reliably working of lithium battery, lithium battery system is appointed The former generation of business decision-making, the sexual behavior that is against any misfortune is significant.

The lithium battery health state evaluation method commonly used at present mainly has:

(1) fully charged (electric discharge) method of testing, this method of testing is simple, but longer during flower, and deep discharge The service life of lithium battery can be affected；

(2) cycle-index Commutation Law: it is a kind of method to estimate service life of lithium battery for access times according to lithium battery, should Method becomes to recycle number of times by equivalent for the life-span of lithium battery, then tries to achieve lithium according to the relation of lithium battery cycle-index and soh The soh of battery.

(3) assessment strategy based on the current characteristic during charging and discharging lithium battery, voltage characteristic and temperature profile, the party Method needs current value, magnitude of voltage and temperature value are calculated, thus again to the current characteristic of lithium battery, voltage characteristic and temperature Feature carries out extracting calculating, and more using algorithm, calculating process is more numerous and diverse, is difficult to calculate accurately；

(4) Impedance Analysis: Impedance Analysis are the soh measuring methods of current forefront, can adopt single-frequency AC signal is measuring the soh of lithium battery, but this method can not reflect the lithium battery soh in full rate cycle；It is right to adopt Lithium battery inputs the signal of different frequency, the data collecting is analyzed to estimate lithium battery parameter and then judge lithium battery Health status, the method accurately, but needs special testing impedance equipment carry out off-line measurement；

(5) empirical model method: the method carries out substantial amounts of experiment to lithium battery, draws soh and the lithium battery of lithium battery The relationship graph of one feature, but the method needs to draw different charts for different lithium batteries, takes longer, limitation Greatly.

Content of the invention

In order to overcome the above-mentioned deficiencies of the prior art, the present invention provides a kind of appraisal procedure of lithium battery health status, with The terminal voltage rate of change of lithium battery, ohmic internal resistance polarization resistance are as lithium battery health status (state of health, soh) Three assessment factors, according to these three assessment factors assess lithium battery health status.

In order to realize foregoing invention purpose, the present invention adopts the following technical scheme that:

The present invention provides a kind of appraisal procedure of lithium battery health status, and methods described includes:

Determine the assessment factor of lithium battery health status；

Calculate the initial value of lithium battery health state evaluation factor weight value；

Calculate the actual value of lithium battery health state evaluation factor weight value；

The health status of assessment lithium battery.

Described lithium battery health state evaluation factor is included in terminal voltage rate of change, ohmic internal resistance and the polarization of lithium battery Resistance.

The described initial value calculating lithium battery health state evaluation factor weight value includes:

The state-of-charge of lithium battery is adjusted to the state-of-charge of setting, and is placed in the temperature environment of setting.

The described initial value calculating lithium battery health state evaluation factor weight value includes:

Determine original state and attenuation state a, b, c of lithium battery, and a, b, c ∈ k, k represents any one of lithium battery Attenuation state；

The described initial value calculating lithium battery health state evaluation factor weight value includes:

Under the original state of lithium battery, lithium battery is made to discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under original state₁₀When, lithium battery stops electric discharge, under original state after now record lithium battery stops discharging Mutation voltage u₂₀, and record terminal voltage u under original state after the δ t second₃₀, then, lithium battery terminal voltage in an initial condition Changing value δ u₀=u₃₀-u₁₀；

Calculate lithium battery terminal voltage rate of change in an initial condition, ohmic internal resistance and polarization resistance, have:

δ₀=δ u₀/δt (1)

r_ω0=(u₂₀-u₁₀)/i (2)

r_d0=(u₃₀-u₂₀)/i (3)

Wherein, δ₀、r_ω0And r_d0It is respectively lithium battery terminal voltage rate of change in an initial condition, ohmic internal resistance and polarization Internal resistance；

Lithium battery, under attenuation state a, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state a_1aWhen, lithium battery stops electric discharge, under attenuation state a after now record lithium battery stops discharging Mutation voltage u_2a, and record terminal voltage u under attenuation state a after the δ t second_3a, then, end under attenuation state a for the lithium battery Voltage change δ u_a=u_3a-u_1a；

Calculate terminal voltage rate of change under attenuation state a for the lithium battery, ohmic internal resistance and polarization resistance, have:

δ_a=δ u_a/δt (4)

r_ωa=(u_2a-u_1a)/i (5)

r_da=(u_3a-u_2a)/i (6)

Wherein, δ_a、r_ωaAnd r_daIt is respectively terminal voltage rate of change under attenuation state a for the lithium battery, ohmic internal resistance and polarization Internal resistance；

Lithium battery, under attenuation state b, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state b_1bWhen, lithium battery stops electric discharge, under attenuation state b after now record lithium battery stops discharging Mutation voltage u_2b, and record terminal voltage u under attenuation state b after the δ t second_3b, then, end under attenuation state b for the lithium battery Voltage change δ u_b=u_3b-u_1b；

Calculate terminal voltage rate of change under attenuation state b for the lithium battery, ohmic internal resistance and polarization resistance, have:

δ_b=δ u_b/δt (7)

r_ωb=(u_2b-u_1b)/i (8)

r_db=(u_3b-u_2b)/i (9)

Wherein, δ_b、r_ωbAnd r_dbIt is respectively terminal voltage rate of change under attenuation state b for the lithium battery, ohmic internal resistance and polarization Internal resistance；

Lithium battery, under attenuation state c, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state c_1cWhen, lithium battery stops electric discharge, under attenuation state c after now record lithium battery stops discharging Mutation voltage u_2c, and record terminal voltage u under attenuation state c after the δ t second_3c, then, end under attenuation state c for the lithium battery Voltage change δ u_c=u_3c-u_1c；

Calculate terminal voltage rate of change under attenuation state c for the lithium battery, ohmic internal resistance and polarization resistance, have:

δ_c=δ u_c/δt (10)

r_ωc=(u_2c-u_1c)/i (11)

r_dc=(u_3c-u_2c)/i (12)

Wherein, δ_c、r_ωcAnd r_dcIt is respectively terminal voltage rate of change under attenuation state c for the lithium battery, ohmic internal resistance and polarization Internal resistance.

The described initial value calculating lithium battery health state evaluation factor weight value includes:

If the initial capacity of lithium battery is q under original state₀, the residual capacity difference of lithium battery under attenuation state a, b, c For q_a、q_bAnd q_c, under attenuation state a, b, c, the health status of lithium battery are expressed as:

${\mathrm{soh}}_a=\frac{q_a}{q_0}*100\%---\left(13\right)$

${\mathrm{soh}}_b=\frac{q_b}{q_0}*100\%---\left(14\right)$

${\mathrm{soh}}_c=\frac{q_c}{q_0}*100\%---\left(15\right)$

Wherein, soh_a、soh_b、soh_cIt is respectively the health status of lithium battery under attenuation state a, b, c.

The described initial value calculating lithium battery health state evaluation factor weight value includes:

According to formula (13)-(18) calculate the terminal voltage rate of change of lithium battery, ohmic internal resistance, the weighted value of polarization resistance just Initial value, has:

${\mathrm{soh}}_a=\[{\mathrm{\λ}}_0\left(\frac{{\mathrm{\δ}}_0}{{\mathrm{\δ}}_a}\right)+{\mathrm{\ρ}}_0\left(\frac{r_{\mathrm{\ω}0}}{r_{\mathrm{\ω}a}}\right)+{\mathrm{\γ}}_0\left(\frac{r_{d0}}{r_{da}}\right)\]*100\%---\left(16\right)$

${\mathrm{soh}}_b=\[{\mathrm{\λ}}_0\left(\frac{{\mathrm{\δ}}_a}{{\mathrm{\δ}}_b}\right)+{\mathrm{\ρ}}_0\left(\frac{r_{\mathrm{\ω}a}}{r_{\mathrm{\ω}b}}\right)+{\mathrm{\γ}}_0\left(\frac{r_{da}}{r_{db}}\right)\]*100\%---\left(17\right)$

${\mathrm{soh}}_c=\[{\mathrm{\λ}}_0\left(\frac{{\mathrm{\δ}}_b}{{\mathrm{\δ}}_c}\right)+{\mathrm{\ρ}}_0\left(\frac{r_{\mathrm{\ω}b}}{r_{\mathrm{\ω}c}}\right)+{\mathrm{\γ}}_0\left(\frac{r_{db}}{r_{dc}}\right)\]*100\%---\left(18\right)$

Wherein, λ₀For the initial value of the weighted value of the terminal voltage rate of change of lithium battery, ρ₀Power for the ohmic internal resistance of lithium battery The initial value of weight values, γ₀Initial value for the weighted value of the polarization resistance of lithium battery.

The described actual value calculating lithium battery health state evaluation factor weight value includes:

Lithium battery, under attenuation state k, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state k_1kWhen, lithium battery stops electric discharge, under attenuation state k after now record lithium battery stops discharging Mutation voltage u_2k, and record terminal voltage u under attenuation state k after the δ t second_3k, then, end under attenuation state k for the lithium battery Voltage change δ u_k=u_3k-u_1k；

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state k for the lithium battery Value, has:

δ_k=δ u_k/δt (19)

r_ωk=(u_2k-u_1k)/i (20)

r_dk=(u_3k-u_2k)/i (21)

Wherein, δ_k、r_ωkAnd r_dkIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization The actual value of internal resistance weighted value；

Lithium battery, under attenuation state k-1, makes lithium battery discharge by pulse current i, is discharged to the terminal voltage of lithium battery For the blanking voltage u under attenuation state k-1_1(k-1)When, lithium battery stops electric discharge, and now record lithium battery is decayed after stopping electric discharge Mutation voltage u under state k-1_2(k-1), and record terminal voltage u under attenuation state k-1 after the δ t second_3(k-1), then, lithium battery Terminal voltage changing value δ u under attenuation state k-1_k-1=u_3(k-1)-u_1(k-1)；

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state k-1 for the lithium battery Actual value, has:

δ_k-1=δ u_k-1/δt (22)

r_ω(k-1)=(u_2(k-1)-u_1(k-1))/i (23)

r_d(k-1)=(u_3(k-1)-u_2(k-1))/i (24)

Wherein, δ_k-1、r_ω(k-1)And r_d(k-1)It is respectively lithium battery in the terminal voltage rate of change under attenuation state k-1, ohm Resistance and the actual value of polarization resistance weighted value；

Lithium battery, under attenuation state i, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state k_1iWhen, lithium battery stops electric discharge, under attenuation state i after now record lithium battery stops discharging Mutation voltage u_2i, and record terminal voltage u under attenuation state i after the δ t second_3i, then, end under attenuation state i for the lithium battery Voltage change δ u_i=u_3i-u_1i；

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state i for the lithium battery Value, has:

δ_i=δ u_i/δt (25)

r_ωi=(u_2i-u_1i)/i (26)

r_di=(u_3i-u_2i)/i (27)

Wherein, δ_i、r_ωiAnd r_diIt is respectively terminal voltage rate of change under attenuation state i for the lithium battery, ohmic internal resistance and polarization The actual value of internal resistance weighted value；

Lithium battery, under attenuation state i-1, makes lithium battery discharge by pulse current i, is discharged to the terminal voltage of lithium battery For the blanking voltage u under attenuation state i-1_1(i-1)When, lithium battery stops electric discharge, and now record lithium battery is decayed after stopping electric discharge Mutation voltage u under state i-1_2(i-1), and record terminal voltage u under attenuation state i-1 after the δ t second_3(i-1), then, lithium battery Terminal voltage changing value δ u under attenuation state i-1_i-1=u_3(i-1)-u_1(i-1)；

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state i-1 for the lithium battery Actual value, has:

δ_i-1=δ u_i-1/δt (28)

r_ω(i-1)=(u_2(i-1)-u_1(i-1))/i (29)

r_d(i-1)=(u_3(i-1)-u_2(i-1))/i (30)

Wherein, δ_i-1、r_ω(i-1)And r_d(i-1)It is respectively lithium battery in the terminal voltage rate of change under attenuation state i-1, ohm Resistance and the actual value of polarization resistance weighted value；

Lithium battery, under attenuation state m, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state m_1mWhen, lithium battery stops electric discharge, under attenuation state m after now record lithium battery stops discharging Mutation voltage u_2m, and record terminal voltage u under attenuation state i after the δ t second_3m, then, end under attenuation state m for the lithium battery Voltage change δ u_m=u_3m-u_1m；

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state m for the lithium battery Value, has:

δ_m=δ u_m/δt (31)

r_ωm=(u_2m-u_1m)/i (32)

r_dm=(u_3m-u_2m)/i (33)

Wherein, δ_m、r_ωmAnd r_dmIt is respectively terminal voltage rate of change under attenuation state m for the lithium battery, ohmic internal resistance and polarization The actual value of internal resistance weighted value.

The described actual value calculating lithium battery health state evaluation factor weight value includes:

Calculate the coefficient of standard deviation of terminal voltage rate of change, ohmic internal resistance and polarization resistance under attenuation state k for the lithium battery, Have:

$v_{1k}=\frac{{\mathrm{\σ}}_{1k}}{\stackrel{\&overbar;}{f_{1k}}}---\left(34\right)$

$v_{2k}=\frac{{\mathrm{\σ}}_{2k}}{\stackrel{\&overbar;}{f_{2k}}}---\left(35\right)$

$v_{3k}=\frac{{\mathrm{\σ}}_{3k}}{\stackrel{\&overbar;}{f_{3k}}}---\left(36\right)$

Wherein, v_1k、v_2kAnd v_3kIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization The coefficient of standard deviation of internal resistance；σ_1k、σ_2kAnd σ_3kBe respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and The standard deviation of polarization resistance, and have For lithium battery attenuation state k and k-1 lower end voltage change ratio ratio meansigma methodss,For lithium battery in attenuation state k With the meansigma methodss of ohmic internal resistance ratio under k-1,For lithium battery under attenuation state k and k-1 polarization resistance ratio average Value, that is,And have i =1,2 ..., k, f_1iFor lithium battery attenuation state i and i-1 lower end voltage change ratio ratio, f_2iFor lithium battery in decay The ratio of ohmic internal resistance, f under state i and i-1_3iFor the ratio of lithium battery polarization resistance under attenuation state i and i-1, that is,

The described actual value calculating lithium battery health state evaluation factor weight value includes:

Calculate terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization resistance weight coefficient, have:

${\mathrm{\λ}}_k=\frac{v_{1k}}{\underset{i=1}{\overset{k}{\σ}}{v}_{1i}}---\left(37\right)$

${\mathrm{\ρ}}_k=\frac{v_{2k}}{\underset{i=1}{\overset{k}{\σ}}{v}_{2i}}---\left(38\right)$

${\mathrm{\γ}}_k=\frac{v_{3k}}{\underset{i=1}{\overset{k}{\σ}}{v}_{3i}}---\left(39\right)$

Wherein, λ_k、ρ_kAnd γ_kIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization The weight coefficient of internal resistance；v_1i、v_2iAnd v_3iIt is respectively the terminal voltage rate of change of lithium battery, ohmic internal resistance and polarization under attenuation state i The coefficient of standard deviation of internal resistance, and haveσ_1i、σ_2iAnd σ_3iIt is respectively under attenuation state i The standard deviation of the terminal voltage rate of change, ohmic internal resistance and polarization resistance of lithium battery, three is expressed as For lithium battery in decay State i and the meansigma methodss of i-1 lower end voltage change ratio ratio,For lithium battery under attenuation state i and i-1 ohmic internal resistance ratio The meansigma methodss of value,For the meansigma methodss of lithium battery polarization resistance ratio under attenuation state i and i-1, that is,And haveM= 1,2 ..., i, f_1mFor lithium battery attenuation state m and m-1 lower end voltage change ratio ratio, f_2mFor lithium battery in decay shape The ratio of ohmic internal resistance, f under state m and m-1_3mFor the ratio of lithium battery polarization resistance under attenuation state m and m-1, that is,

The health status of described assessment lithium battery include:

Calculate health status under attenuation state k for the lithium battery, have:

soh_k=(λ_k*f_1k+ρ_k*f_2k+γ_k*f_3k) * 100% (40)

Wherein, soh_kFor health status under attenuation state k for the lithium battery, soh_kBigger, show that lithium battery health status are got over Good.

Compared with immediate prior art, the technical scheme that the present invention provides has the advantages that

1st, achieve the quick and precisely measurement of lithium battery health status；

2nd, changing features (the terminal voltage rate of change of lithium battery) and interior changing features (ohmic internal resistance and pole outside comprehensive lithium battery Change internal resistance) as assessment factor, improve the accuracy of lithium battery health state evaluation；

3rd, using after pulsed discharge terminates, measuring and calculate lithium battery terminal voltage rate of change, ohmic internal resistance and pole simultaneously Change the method for internal resistance it is ensured that the state homogeneity of lithium battery state measurement and time consistency, improve lithium battery health shape The accuracy of state assessment factor；

4th, different assessment factors adopt different weights, and in lithium battery attenuation process, according to different assessment factors Change adjustment weighted value, improve the accuracy of lithium battery health state evaluation；

5th, adopt coefficient of standard deviation to calculate the weight coefficient of lithium battery health state evaluation factor, be not subject to assessment factor physics The impact of unit；

6th, method combines the standard deviation of assessment factor and the impact of average figureofmerit, preferably reflects assessment factor Overall mark variable extent in varying level.

Brief description

Fig. 1 is the time dependent performance plot of voltage when pulse current makes lithium battery discharge in the embodiment of the present invention；

Fig. 2 is the time dependent performance plot of pulse current in the embodiment of the present invention.

Specific embodiment

Below in conjunction with the accompanying drawings the present invention is described in further detail.

In the ageing process of lithium battery, due to the reduction of lithium battery interior species activity, resistance becomes big, the appearance of lithium battery The rate of change of amount and lithium battery terminal voltage all can change, and can be measured strong according to the relation of lithium battery terminal voltage and capacity Health state soh (state of health, soh).This measuring method is simple and quick, but individually uses the change of lithium battery terminal voltage There is certain deviation come the health status to judge lithium battery in speed；Internal resistance due to lithium battery there is also certain relation with soh, Soh is lower, and lithium battery internal resistance is bigger, by data such as detection voltage, electric current, temperature, can indirectly calculate the interior of lithium battery Resistance, then calculates according to the relation of soh and lithium battery internal resistance and tries to achieve soh.But the internal resistance of lithium battery is in soh excursion not Change inconspicuous when big, and when aging of lithium battery is serious the changing greatly of resistance value, thus the method is when soh change is less The error of measurement can be larger.

The invention discloses under a kind of pulse current effect of the fixation at for employing lithium battery, measurement lithium battery electric discharge The change of the terminal voltage value to after the blanking voltage of a fixation, thus drawing terminal voltage rate of change, as lithium battery health One assessment factor of state, then calculate the internal resistance (include ohmic internal resistance and polarization resistance) of lithium battery as another two assessment because Element, is added the health status judging lithium battery later using these three assessment factor weights.Using lithium battery terminal voltage rate of change As the outer characteristic parameter carrying out lithium battery health state evaluation；Commented as carrying out lithium battery health status using lithium battery internal resistance The interior characteristic parameter estimated, meanwhile, for being more conducive to calculate analysis, lithium battery internal resistance is decomposed into ohmic internal resistance and polarization resistance, with As comprehensive assessment parameter after these three assessment parameters weighting additions, and the change with state during aging of lithium battery, Constantly the weight of three assessment parameters of adjustment, to revise comprehensive assessment parameter with this；It is capable of lithium battery by the method to be good for The Online Judge of health state, the conventional single parameter of ratio, more accurately, improve the safety during lithium battery uses.

1. the present invention proposes an assessment factor using lithium battery terminal voltage rate of change as lithium battery health status.

During lithium battery circular flow, with the increase of cycle-index or operating mode run time, lithium battery gradually declines Subtract, in mutually synthermal and state-of-charge, pulse current discharging is applied on lithium battery and stand to same breakdown voltage, lithium is electric The rate of change of pond terminal voltage simultaneously differs, and tests and calculate rate of change an important criterion in this, as lithium battery soh.

2. the present invention proposes the ohmic internal resistance testing and calculating lithium battery using pulse current and polarization resistance, with ohm Internal resistance and polarization resistance are as the another two assessment factor of lithium battery health status.

3. the present invention proposes according to three assessment factors calculated in 1 and 2, in addition different weighted values, and according to The differential declines degree of lithium battery, adjusts weighted value, accurately calculates the health status of lithium battery in life cycle management.

The present invention provides a kind of appraisal procedure of lithium battery health status, and methods described includes:

Determine the assessment factor of lithium battery health status；

Calculate the initial value of lithium battery health state evaluation factor weight value；

Calculate the actual value of lithium battery health state evaluation factor weight value；

The health status of assessment lithium battery.

Described lithium battery health state evaluation factor is included in terminal voltage rate of change, ohmic internal resistance and the polarization of lithium battery Resistance.

The described initial value calculating lithium battery health state evaluation factor weight value includes:

The state-of-charge of lithium battery is adjusted to the state-of-charge of setting, and is placed in the temperature environment of setting.

The described initial value calculating lithium battery health state evaluation factor weight value includes:

Determine original state and attenuation state a, b, c of lithium battery, and a, b, c ∈ k, k represents any one of lithium battery Attenuation state；

The described initial value calculating lithium battery health state evaluation factor weight value includes:

Under the original state of lithium battery, lithium battery is made to discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under original state₁₀When, lithium battery stops electric discharge, under original state after now record lithium battery stops discharging Mutation voltage u₂₀, and record terminal voltage u under original state after the δ t second₃₀, then, lithium battery terminal voltage in an initial condition Changing value δ u₀=u₃₀-u₁₀；

Calculate lithium battery terminal voltage rate of change in an initial condition, ohmic internal resistance and polarization resistance, have:

δ₀=δ u₀/δt (1)

r_ω0=(u₂₀-u₁₀)/i (2)

r_d0=(u₃₀-u₂₀)/i (3)

Wherein, δ₀、r_ω0And r_d0It is respectively lithium battery terminal voltage rate of change in an initial condition, ohmic internal resistance and polarization Internal resistance；

Lithium battery, under attenuation state a, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state a_1aWhen, lithium battery stops electric discharge, under attenuation state a after now record lithium battery stops discharging Mutation voltage u_2a, and record terminal voltage u under attenuation state a after the δ t second_3a, then, end under attenuation state a for the lithium battery Voltage change δ u_a=u_3a-u_1a；

Calculate terminal voltage rate of change under attenuation state a for the lithium battery, ohmic internal resistance and polarization resistance, have:

δ_a=δ u_a/δt (4)

r_ωa=(u_2a-u_1a)/i (5)

r_da=(u_3a-u_2a)/i (6)

Wherein, δ_a、r_ωaAnd r_daIt is respectively terminal voltage rate of change under attenuation state a for the lithium battery, ohmic internal resistance and polarization Internal resistance；

Lithium battery, under attenuation state b, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state b_1bWhen, lithium battery stops electric discharge, under attenuation state b after now record lithium battery stops discharging Mutation voltage u_2b, and record terminal voltage u under attenuation state b after the δ t second_3b, then, end under attenuation state b for the lithium battery Voltage change δ u_b=u_3b-u_1b；

Calculate terminal voltage rate of change under attenuation state b for the lithium battery, ohmic internal resistance and polarization resistance, have:

δ_b=δ u_b/δt (7)

r_ωb=(u_2b-u_1b)/i (8)

r_db=(u_3b-u_2b)/i (9)

Wherein, δ_b、r_ωbAnd r_dbIt is respectively terminal voltage rate of change under attenuation state b for the lithium battery, ohmic internal resistance and polarization Internal resistance；

Lithium battery, under attenuation state c, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state c_1cWhen, lithium battery stops electric discharge, under attenuation state c after now record lithium battery stops discharging Mutation voltage u_2c, and record terminal voltage u under attenuation state c after the δ t second_3c, then, end under attenuation state c for the lithium battery Voltage change δ u_c=u_3c-u_1c；

Calculate terminal voltage rate of change under attenuation state c for the lithium battery, ohmic internal resistance and polarization resistance, have:

δ_c=δ u_c/δt (10)

r_ωc=(u_2c-u_1c)/i (11)

r_dc=(u_3c-u_2c)/i (12)

Wherein, δ_c、r_ωcAnd r_dcIt is respectively terminal voltage rate of change under attenuation state c for the lithium battery, ohmic internal resistance and polarization Internal resistance.

The described initial value calculating lithium battery health state evaluation factor weight value includes:

If the initial capacity of lithium battery is q under original state₀, the residual capacity difference of lithium battery under attenuation state a, b, c For q_a、q_bAnd q_c, under attenuation state a, b, c, the health status of lithium battery are expressed as:

${\mathrm{soh}}_a=\frac{q_a}{q_0}*100\%---\left(13\right)$

${\mathrm{soh}}_b=\frac{q_b}{q_0}*100\%---\left(14\right)$

${\mathrm{soh}}_c=\frac{q_c}{q_0}*100\%---\left(15\right)$

Wherein, soh_a、soh_b、soh_cIt is respectively the health status of lithium battery under attenuation state a, b, c.

The described initial value calculating lithium battery health state evaluation factor weight value includes:

According to formula (13)-(18) calculate the terminal voltage rate of change of lithium battery, ohmic internal resistance, the weighted value of polarization resistance just Initial value, has:

${\mathrm{soh}}_a=\[{\mathrm{\λ}}_0\left(\frac{{\mathrm{\δ}}_0}{{\mathrm{\δ}}_a}\right)+{\mathrm{\ρ}}_0\left(\frac{r_{\mathrm{\ω}0}}{r_{\mathrm{\ω}a}}\right)+{\mathrm{\γ}}_0\left(\frac{r_{d0}}{r_{da}}\right)\]*100\%---\left(16\right)$

${\mathrm{soh}}_b=\[{\mathrm{\λ}}_0\left(\frac{{\mathrm{\δ}}_a}{{\mathrm{\δ}}_b}\right)+{\mathrm{\ρ}}_0\left(\frac{r_{\mathrm{\ω}a}}{r_{\mathrm{\ω}b}}\right)+{\mathrm{\γ}}_0\left(\frac{r_{da}}{r_{db}}\right)\]*100\%---\left(17\right)$

${\mathrm{soh}}_c=\[{\mathrm{\λ}}_0\left(\frac{{\mathrm{\δ}}_b}{{\mathrm{\δ}}_c}\right)+{\mathrm{\ρ}}_0\left(\frac{r_{\mathrm{\ω}b}}{r_{\mathrm{\ω}c}}\right)+{\mathrm{\γ}}_0\left(\frac{r_{db}}{r_{dc}}\right)\]*100\%---\left(18\right)$

Wherein, λ₀For the initial value of the weighted value of the terminal voltage rate of change of lithium battery, ρ₀Power for the ohmic internal resistance of lithium battery The initial value of weight values, γ₀Initial value for the weighted value of the polarization resistance of lithium battery.

The described actual value calculating lithium battery health state evaluation factor weight value includes:

Lithium battery, under attenuation state k, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state k_1kWhen, lithium battery stops electric discharge, under attenuation state k after now record lithium battery stops discharging Mutation voltage u_2k, and record terminal voltage u under attenuation state k after the δ t second_3k, then, end under attenuation state k for the lithium battery Voltage change δ u_k=u_3k-u_1k；To a certain model lithium battery, i, u_1kIdentical is taken to fix with δ t in whole evaluation process Value；The time dependent performance plot of voltage when Fig. 1 represents that pulse current makes lithium battery discharge, horizontal axis representing time, longitudinal axis table Show voltage；Fig. 2 represents the time dependent performance plot of pulse current, horizontal axis representing time, and the longitudinal axis represents electric current.

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state k for the lithium battery Value, has:

δ_k=δ u_k/δt (19)

r_ωk=(u_2k-u_1k)/i (20)

r_dk=(u_3k-u_2k)/i (21)

Wherein, δ_k、r_ωkAnd r_dkIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization The actual value of internal resistance weighted value；

Lithium battery, under attenuation state k-1, makes lithium battery discharge by pulse current i, is discharged to the terminal voltage of lithium battery For the blanking voltage u under attenuation state k-1_1(k-1)When, lithium battery stops electric discharge, and now record lithium battery is decayed after stopping electric discharge Mutation voltage u under state k-1_2(k-1), and record terminal voltage u under attenuation state k-1 after the δ t second_3(k-1), then, lithium battery Terminal voltage changing value δ u under attenuation state k-1_k-1=u_3(k-1)-u_1(k-1)；

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state k-1 for the lithium battery Actual value, has:

δ_k-1=δ u_k-1/δt (22)

r_ω(k-1)=(u_2(k-1)-u_1(k-1))/i (23)

r_d(k-1)=(u_3(k-1)-u_2(k-1))/i (24)

Wherein, δ_k-1、r_ω(k-1)And r_d(k-1)It is respectively lithium battery in the terminal voltage rate of change under attenuation state k-1, ohm Resistance and the actual value of polarization resistance weighted value；

Lithium battery, under attenuation state i, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state k_1iWhen, lithium battery stops electric discharge, under attenuation state i after now record lithium battery stops discharging Mutation voltage u_2i, and record terminal voltage u under attenuation state i after the δ t second_3i, then, end under attenuation state i for the lithium battery Voltage change δ u_i=u_3i-u_1i；

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state i for the lithium battery Value, has:

δ_i=δ u_i/δt (25)

r_ωi=(u_2i-u_1i)/i (26)

r_di=(u_3i-u_2i)/i (27)

Wherein, δ_i、r_ωiAnd r_diIt is respectively terminal voltage rate of change under attenuation state i for the lithium battery, ohmic internal resistance and polarization The actual value of internal resistance weighted value；

Lithium battery, under attenuation state i-1, makes lithium battery discharge by pulse current i, is discharged to the terminal voltage of lithium battery For the blanking voltage u under attenuation state i-1_1(i-1)When, lithium battery stops electric discharge, and now record lithium battery is decayed after stopping electric discharge Mutation voltage u under state i-1_2(i-1), and record terminal voltage u under attenuation state i-1 after the δ t second_3(i-1), then, lithium battery Terminal voltage changing value δ u under attenuation state i-1_i-1=u_3(i-1)-u_1(i-1)；

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state i-1 for the lithium battery Actual value, has:

δ_i-1=δ u_i-1/δt (28)

r_ω(i-1)=(u_2(i-1)-u_1(i-1))/i (29)

r_d(i-1)=(u_3(i-1)-u_2(i-1))/i (30)

Wherein, δ_i-1、r_ω(i-1)And r_d(i-1)It is respectively lithium battery in the terminal voltage rate of change under attenuation state i-1, ohm Resistance and the actual value of polarization resistance weighted value；

Lithium battery, under attenuation state m, makes lithium battery discharge by pulse current i, the terminal voltage being discharged to lithium battery is Blanking voltage u under attenuation state m_1mWhen, lithium battery stops electric discharge, under attenuation state m after now record lithium battery stops discharging Mutation voltage u_2m, and record terminal voltage u under attenuation state i after the δ t second_3m, then, end under attenuation state m for the lithium battery Voltage change δ u_m=u_3m-u_1m；

Calculate the reality of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state m for the lithium battery Value, has:

δ_m=δ u_m/δt (31)

r_ωm=(u_2m-u_1m)/i (32)

r_dm=(u_3m-u_2m)/i (33)

Wherein, δ_m、r_ωmAnd r_dmIt is respectively terminal voltage rate of change under attenuation state m for the lithium battery, ohmic internal resistance and polarization The actual value of internal resistance weighted value.

The described actual value calculating lithium battery health state evaluation factor weight value includes:

Calculate the coefficient of standard deviation of terminal voltage rate of change, ohmic internal resistance and polarization resistance under attenuation state k for the lithium battery, Have:

$v_{1k}=\frac{{\mathrm{\σ}}_{1k}}{\stackrel{\&overbar;}{f_{1k}}}---\left(34\right)$

$v_{2k}=\frac{{\mathrm{\σ}}_{2k}}{\stackrel{\&overbar;}{f_{2k}}}---\left(35\right)$

$v_{3k}=\frac{{\mathrm{\σ}}_{3k}}{\stackrel{\&overbar;}{f_{3k}}}---\left(36\right)$

Wherein, v_1k、v_2kAnd v_3kIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization The coefficient of standard deviation of internal resistance；σ_1k、σ_2kAnd σ_3kBe respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and The standard deviation of polarization resistance, and have For lithium battery attenuation state k and k-1 lower end voltage change ratio ratio meansigma methodss,For lithium battery in attenuation state k With the meansigma methodss of ohmic internal resistance ratio under k-1,For lithium battery under attenuation state k and k-1 polarization resistance ratio average Value, that is,And have i =1,2 ..., k, f_1iFor lithium battery attenuation state i and i-1 lower end voltage change ratio ratio, f_2iFor lithium battery in decay The ratio of ohmic internal resistance, f under state i and i-1_3iFor the ratio of lithium battery polarization resistance under attenuation state i and i-1, that is,

The described actual value calculating lithium battery health state evaluation factor weight value includes:

Calculate terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization resistance weight coefficient, have:

${\mathrm{\λ}}_k=\frac{v_{1k}}{\underset{i=1}{\overset{k}{\σ}}{v}_{1i}}---\left(37\right)$

${\mathrm{\ρ}}_k=\frac{v_{2k}}{\underset{i=1}{\overset{k}{\σ}}{v}_{2i}}---\left(38\right)$

${\mathrm{\γ}}_k=\frac{v_{3k}}{\underset{i=1}{\overset{k}{\σ}}{v}_{3i}}---\left(39\right)$

Wherein, λ_k、ρ_kAnd γ_kIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization The weight coefficient of internal resistance；v_1i、v_2iAnd v_3iIt is respectively the terminal voltage rate of change of lithium battery, ohmic internal resistance and polarization under attenuation state i The coefficient of standard deviation of internal resistance, and haveσ_1i、σ_2iAnd σ_3iIt is respectively lithium electricity under attenuation state i The standard deviation of the terminal voltage rate of change, ohmic internal resistance and polarization resistance in pond, three is expressed as For lithium battery under attenuation state i and i-1 terminal voltage The meansigma methodss of rate of change ratio,For the meansigma methodss of lithium battery ohmic internal resistance ratio under attenuation state i and i-1,For lithium electricity The meansigma methodss of pond polarization resistance ratio under attenuation state i and i-1, that is,And HaveM=1,2 ..., i, f_1mFor lithium battery in attenuation state m and The ratio of m-1 lower end voltage change ratio, f_2mFor the ratio of lithium battery ohmic internal resistance under attenuation state m and m-1, f_3mFor lithium electricity The ratio of pond polarization resistance under attenuation state m and m-1, that is,

The health status of described assessment lithium battery include:

Calculate health status under attenuation state k for the lithium battery, have:

soh_k=(λ_k*f_1k+ρ_k*f_2k+γ_k*f_3k) * 100% (40)

Wherein, soh_kFor health status under attenuation state k for the lithium battery, soh_kBigger, show that lithium battery health status are got over Good.

Finally it should be noted that: above example is only not intended to limit in order to technical scheme to be described, institute The those of ordinary skill in genus field still the specific embodiment of the present invention can be modified with reference to above-described embodiment or Equivalent, these are all applying for pending this without departing from any modification of spirit and scope of the invention or equivalent Within bright claims.

Claims (11)

1. a kind of appraisal procedure of lithium battery health status is it is characterised in that methods described includes:

Determine the assessment factor of lithium battery health status；

Calculate the initial value of lithium battery health state evaluation factor weight value；

Calculate the actual value of lithium battery health state evaluation factor weight value；

The health status of assessment lithium battery.

2. lithium battery health status according to claim 1 appraisal procedure it is characterised in that described lithium battery health shape State assessment factor includes terminal voltage rate of change, ohmic internal resistance and the polarization resistance of lithium battery.

3. the appraisal procedure of lithium battery health status according to claim 2 is it is characterised in that described calculating lithium battery is good for The initial value of health state estimation factor weight value includes:

The state-of-charge of lithium battery is adjusted to the state-of-charge of setting, and is placed in the temperature environment of setting.

4. the appraisal procedure of lithium battery health status according to claim 3 is it is characterised in that described calculating lithium battery is good for The initial value of health state estimation factor weight value includes:

Determine original state and attenuation state a, b, c of lithium battery, and a, b, c ∈ k, k represents any one decay of lithium battery State.

5. the appraisal procedure of lithium battery health status according to claim 4 is it is characterised in that described calculating lithium battery is good for The initial value of health state estimation factor weight value includes:

Under the original state of lithium battery, lithium battery is made to discharge by pulse current i, the terminal voltage being discharged to lithium battery is initial Blanking voltage u under state₁₀When, lithium battery stops electric discharge, the mutation under original state after now record lithium battery stops discharging Voltage u₂₀, and record terminal voltage u under original state after the δ t second₃₀, then, lithium battery terminal voltage change in an initial condition Value δ u₀=u₃₀-u₁₀；

Calculate lithium battery terminal voltage rate of change in an initial condition, ohmic internal resistance and polarization resistance, have:

δ₀=δ u₀/δt (1)

r_ω0=(u₂₀-u₁₀)/i (2)

r_d0=(u₃₀-u₂₀)/i (3)

Wherein, δ₀、r_ω0And r_d0It is respectively lithium battery terminal voltage rate of change in an initial condition, ohmic internal resistance and polarization resistance；

Lithium battery, under attenuation state a, makes lithium battery discharge by pulse current i, and the terminal voltage being discharged to lithium battery is decay Blanking voltage u under state a_1aWhen, lithium battery stops electric discharge, prominent under attenuation state a after now record lithium battery stops discharging Time variant voltage u_2a, and record terminal voltage u under attenuation state a after the δ t second_3a, then, terminal voltage under attenuation state a for the lithium battery Changing value δ u_a=u_3a-u_1a；

Calculate terminal voltage rate of change under attenuation state a for the lithium battery, ohmic internal resistance and polarization resistance, have:

δ_a=δ u_a/δt (4)

r_ωa=(u_2a-u_1a)/i (5)

r_da=(u_3a-u_2a)/i (6)

Wherein, δ_a、r_ωaAnd r_daIt is respectively terminal voltage rate of change under attenuation state a for the lithium battery, ohmic internal resistance and polarization resistance；

Lithium battery, under attenuation state b, makes lithium battery discharge by pulse current i, and the terminal voltage being discharged to lithium battery is decay Blanking voltage u under state b_1bWhen, lithium battery stops electric discharge, prominent under attenuation state b after now record lithium battery stops discharging Time variant voltage u_2b, and record terminal voltage u under attenuation state b after the δ t second_3b, then, terminal voltage under attenuation state b for the lithium battery Changing value δ u_b=u_3b-u_1b；

Calculate terminal voltage rate of change under attenuation state b for the lithium battery, ohmic internal resistance and polarization resistance, have:

δ_b=δ u_b/δt (7)

r_ωb=(u_2b-u_1b)/i (8)

r_db=(u_3b-u_2b)/i (9)

Wherein, δ_b、r_ωbAnd r_dbIt is respectively lithium battery in the terminal voltage rate of change under attenuation state b, ohmic internal resistance and polarization Resistance；

Lithium battery, under attenuation state c, makes lithium battery discharge by pulse current i, and the terminal voltage being discharged to lithium battery is decay Blanking voltage u under state c_1cWhen, lithium battery stops electric discharge, prominent under attenuation state c after now record lithium battery stops discharging Time variant voltage u_2c, and record terminal voltage u under attenuation state c after the δ t second_3c, then, terminal voltage under attenuation state c for the lithium battery Changing value δ u_c=u_3c-u_1c；

Calculate terminal voltage rate of change under attenuation state c for the lithium battery, ohmic internal resistance and polarization resistance, have:

δ_c=δ u_c/δt (10)

r_ωc=(u_2c-u_1c)/i (11)

r_dc=(u_3c-u_2c)/i (12)

Wherein, δ_c、r_ωcAnd r_dcIt is respectively terminal voltage rate of change under attenuation state c for the lithium battery, ohmic internal resistance and polarization resistance.

6. the appraisal procedure of lithium battery health status according to claim 5 is it is characterised in that described calculating lithium battery is good for The initial value of health state estimation factor weight value includes:

If the initial capacity of lithium battery is q under original state₀, under attenuation state a, b, c, the residual capacity of lithium battery is respectively q_a、 q_bAnd q_c, under attenuation state a, b, c, the health status of lithium battery are expressed as:

Wherein, soh_a、soh_b、soh_cIt is respectively the health status of lithium battery under attenuation state a, b, c.

7. the appraisal procedure of lithium battery health status according to claim 6 is it is characterised in that described calculating lithium battery is good for The initial value of health state estimation factor weight value includes:

According to formula (13)-(18) calculate the terminal voltage rate of change of lithium battery, ohmic internal resistance, the weighted value of polarization resistance initial Value, has:

Wherein, λ₀For the initial value of the weighted value of the terminal voltage rate of change of lithium battery, ρ₀Weighted value for the ohmic internal resistance of lithium battery Initial value, γ₀Initial value for the weighted value of the polarization resistance of lithium battery.

8. the appraisal procedure of lithium battery health status according to claim 7 is it is characterised in that described calculating lithium battery is good for The actual value of health state estimation factor weight value includes:

Lithium battery, under attenuation state k, makes lithium battery discharge by pulse current i, and the terminal voltage being discharged to lithium battery is decay Blanking voltage u under state k_1kWhen, lithium battery stops electric discharge, prominent under attenuation state k after now record lithium battery stops discharging Time variant voltage u_2k, and record terminal voltage u under attenuation state k after the δ t second_3k, then, terminal voltage under attenuation state k for the lithium battery Changing value δ u_k=u_3k-u_1k；

Calculate the actual value of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state k for the lithium battery, Have:

δ_k=δ u_k/δt (19)

r_ωk=(u_2k-u_1k)/i (20)

r_dk=(u_3k-u_2k)/i (21)

Wherein, δ_k、r_ωkAnd r_dkIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization resistance The actual value of weighted value；

Lithium battery, under attenuation state k-1, makes lithium battery discharge by pulse current i, and the terminal voltage being discharged to lithium battery is to decline Subtract the blanking voltage u under state k-1_1(k-1)When, lithium battery stops electric discharge, and now record lithium battery stops attenuation state after electric discharge Mutation voltage u under k-1_2(k-1), and record terminal voltage u under attenuation state k-1 after the δ t second_3(k-1), then, lithium battery is declining Subtract the terminal voltage changing value δ u under state k-1_k-1=u_3(k-1)-u_1(k-1)；

Calculate the actual value of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state k-1 for the lithium battery, Have:

δ_k-1=δ u_k-1/δt (22)

r_ω(k-1)=(u_2(k-1)-u_1(k-1))/i (23)

r_d(k-1)=(u_3(k-1)-u_2(k-1))/i (24)

Wherein, δ_k-1、r_ω(k-1)And r_d(k-1)Be respectively terminal voltage rate of change under attenuation state k-1 for the lithium battery, ohmic internal resistance and The actual value of polarization resistance weighted value；

Lithium battery, under attenuation state i, makes lithium battery discharge by pulse current i, and the terminal voltage being discharged to lithium battery is decay Blanking voltage u under state k_1iWhen, lithium battery stops electric discharge, prominent under attenuation state i after now record lithium battery stops discharging Time variant voltage u_2i, and record terminal voltage u under attenuation state i after the δ t second_3i, then, terminal voltage under attenuation state i for the lithium battery Changing value δ u_i=u_3i-u_1i；

Calculate the actual value of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state i for the lithium battery, Have:

δ_i=δ u_i/δt (25)

r_ωi=(u_2i-u_1i)/i (26)

r_di=(u_3i-u_2i)/i (27)

Wherein, δ_i、r_ωiAnd r_diIt is respectively terminal voltage rate of change under attenuation state i for the lithium battery, ohmic internal resistance and polarization resistance The actual value of weighted value；

Lithium battery, under attenuation state i-1, makes lithium battery discharge by pulse current i, and the terminal voltage being discharged to lithium battery is to decline Subtract the blanking voltage u under state i-1_1(i-1)When, lithium battery stops electric discharge, and now record lithium battery stops attenuation state after electric discharge Mutation voltage u under i-1_2(i-1), and record terminal voltage u under attenuation state i-1 after the δ t second_3(i-1), then, lithium battery is declining Subtract the terminal voltage changing value δ u under state i-1_i-1=u_3(i-1)-u_1(i-1)；

Calculate the actual value of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state i-1 for the lithium battery, Have:

δ_i-1=δ u_i-1/δt (28)

r_ω(i-1)=(u_2(i-1)-u_1(i-1))/i (29)

r_d(i-1)=(u_3(i-1)-u_2(i-1))/i (30)

Wherein, δ_i-1、r_ω(i-1)And r_d(i-1)Be respectively terminal voltage rate of change under attenuation state i-1 for the lithium battery, ohmic internal resistance and The actual value of polarization resistance weighted value；

Lithium battery, under attenuation state m, makes lithium battery discharge by pulse current i, and the terminal voltage being discharged to lithium battery is decay Blanking voltage u under state m_1mWhen, lithium battery stops electric discharge, prominent under attenuation state m after now record lithium battery stops discharging Time variant voltage u_2m, and record terminal voltage u under attenuation state i after the δ t second_3m, then, terminal voltage under attenuation state m for the lithium battery Changing value δ u_m=u_3m-u_1m；

Calculate the actual value of terminal voltage rate of change, ohmic internal resistance and polarization resistance weighted value under attenuation state m for the lithium battery, Have:

δ_m=δ u_m/δt (31)

r_ωm=(u_2m-u_1m)/i (32)

r_dm=(u_3m-u_2m)/i (33)

Wherein, δ_m、r_ωmAnd r_dmIt is respectively terminal voltage rate of change under attenuation state m for the lithium battery, ohmic internal resistance and polarization resistance The actual value of weighted value.

9. the appraisal procedure of lithium battery health status according to claim 8 is it is characterised in that described calculating lithium battery is good for The actual value of health state estimation factor weight value includes:

Calculate the coefficient of standard deviation of terminal voltage rate of change, ohmic internal resistance and polarization resistance under attenuation state k for the lithium battery, have:

Wherein, v_1k、v_2kAnd v_3kIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization resistance Coefficient of standard deviation；σ_1k、σ_2kAnd σ_3kIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization The standard deviation of internal resistance, and have For lithium battery attenuation state k and k-1 lower end voltage change ratio ratio meansigma methodss,For lithium battery in attenuation state k and k- The meansigma methodss of 1 time ohmic internal resistance ratio,For the meansigma methodss of lithium battery polarization resistance ratio under attenuation state k and k-1, that is,And have I=1, 2 ..., k, f_1iFor lithium battery attenuation state i and i-1 lower end voltage change ratio ratio, f_2iFor lithium battery in attenuation state i With the ratio of ohmic internal resistance under i-1, f_3iFor the ratio of lithium battery polarization resistance under attenuation state i and i-1, that is,

10. the appraisal procedure of lithium battery health status according to claim 9 is it is characterised in that described calculating lithium battery The actual value of health state evaluation factor weight value includes:

Calculate terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization resistance weight coefficient, have:

Wherein, λ_k、ρ_kAnd γ_kIt is respectively terminal voltage rate of change under attenuation state k for the lithium battery, ohmic internal resistance and polarization resistance Weight coefficient；v_1i、v_2iAnd v_3iIt is respectively the terminal voltage rate of change of lithium battery, ohmic internal resistance and polarization resistance under attenuation state i Coefficient of standard deviation, and haveσ_1i、σ_2iAnd σ_3iIt is respectively lithium battery under attenuation state i Terminal voltage rate of change, ohmic internal resistance and polarization resistance standard deviation, three is expressed as For lithium battery under attenuation state i and i-1 terminal voltage The meansigma methodss of rate of change ratio,For the meansigma methodss of lithium battery ohmic internal resistance ratio under attenuation state i and i-1,For lithium electricity The meansigma methodss of pond polarization resistance ratio under attenuation state i and i-1, that is,And HaveM=1,2 ..., i, f_1mFor lithium battery in attenuation state m and The ratio of m-1 lower end voltage change ratio, f_2mFor the ratio of lithium battery ohmic internal resistance under attenuation state m and m-1, f_3mFor lithium electricity The ratio of pond polarization resistance under attenuation state m and m-1, that is,

The appraisal procedure of 11. lithium battery health status according to claim 10 is it is characterised in that described assessment lithium battery Health status include:

Calculate health status under attenuation state k for the lithium battery, have:

soh_k=(λ_k*f_1k+ρ_k*f_2k+γ_k*f_3k) * 100% (40)

Wherein, soh_kFor health status under attenuation state k for the lithium battery, soh_kBigger, show that lithium battery health status are better.