CN105203846A - Method for eliminating influences of low temperature on testing of internal resistance of energy storage battery - Google Patents

Abstract

The invention discloses a method for eliminating influences of the low temperature on testing of the internal resistance of an energy storage battery, and relates to the technical field of battery managing. The method aims at solving the problem that the temperature influences testing of the internal resistance of the energy storage battery. According to the method for eliminating the influences of the low temperature on testing of the internal resistance of the energy storage battery, the function relationship of changes of the internal resistance of the energy storage battery along with changes of the temperature is created in theory, the measured temperature of the battery is substituted into the relational expression, it is accordingly achieved that the measured internal resistance value of the battery is normalized at the standard temperature, and the aim of eliminating the influences of the temperature on testing of the internal resistance of the battery is achieved accordingly. Meanwhile, the method is suitable for batteries at different environment temperatures and batteries with different aging degrees.

Description

A kind of method eliminated low temperature and energy-storage battery inner walkway is affected

Technical field

The invention belongs to technical field of battery management, particularly relate to a kind of method eliminated low temperature and energy-storage battery inner walkway is affected.

Background technology

The power that the measurement of energy-storage battery internal resistance is widely used in battery is estimated, health status is estimated, and battery failures such as to examine at multiple field.But the internal resistance of battery is very responsive to temperature, namely when testing the internal resistance of battery, temperature can produce strong impact to resistance, and this brings difficulty to the measurement of the internal resistance of cell and application.

Summary of the invention

The present invention is the problem affecting energy-storage battery inner walkway in order to solve temperature, now provides a kind of method eliminated low temperature and affect energy-storage battery inner walkway.

Eliminate the method that low temperature affects energy-storage battery inner walkway, the method is:

Step one: the functional equation setting up temperature variation and internal resistance variable quantity:

$\begin{array}{c}{\mathrm{\ΔR}}_o={\mathrm{\ΔR}}_{bulk}+{\mathrm{\ΔR}}_{SEI}+{\mathrm{\ΔR}}_{ct}\\ =k_{bulk}(T-T_{std})+k_{SEI}(T-T_{std})+k_{ct}(\frac{1}{e^{-E_a/(T+273)}}-\frac{1}{e^{-E_a/(T_{std}+273)}})\end{array}$

Wherein, Δ R _ofor energy-storage battery internal resistance variable quantity, Δ R _bulkfor the variable quantity of bulk resistor, Δ R _sEIfor the variable quantity of SEI resistance, Δ R _ctfor the variable quantity of charge transfer resistance, T is actual temperature, T _stdfor standard temperature, E _afor apparent activation energy, k _bulk, k _sEI, k _ctbe respectively the temperature coefficient of bulk resistor, SEI resistance, charge transfer resistance;

Carry out arranging to above formula and obtain the functional equation after arranging:

${\mathrm{\ΔR}}_o={\mathrm{\κ}}_{1}T+{\mathrm{\κ}}_2{e}^{{\mathrm{\κ}}_3/(T+273)}+{\mathrm{\κ}}_4$

Wherein, κ ₁for combined temperature coefficient, the κ of bulk resistor and SEI resistance ₂for the temperature coefficient of charge transfer resistance, κ ₃for energy of activation coefficient, κ ₄for the resnstance transformer coefficient under standard temperature;

Step 2: obtain different temperatures by experiment, the energy-storage battery internal resistance of different ageing step is subject to the variable quantity that temperature affects, and according to this variable quantity to coefficient κ ₁, κ ₂, κ ₃, κ ₄carry out matching, obtain the functional equation after matching;

Step 3: environment temperature is measured, and this ambient temperature measurement value is brought in the functional equation after the matching of step 2 acquisition, obtain the energy-storage battery internal resistance variable quantity caused by temperature variation, utilize this energy-storage battery internal resistance variable quantity to eliminate temperature to the impact of energy-storage battery internal resistance.

Above-mentioned standard temperature T _stdit is 30 DEG C.

A kind of method eliminated low temperature and energy-storage battery inner walkway is affected of the present invention, establish the temperature variant funtcional relationship of energy-storage battery internal resistance theoretically, by measurement battery temperature is brought in relational expression, thus under realizing that surveyed internal resistance of cell value is normalized to standard temperature, thus realize eliminating temperature to the object of the impact that the internal resistance of cell is tested.Meanwhile, this method is applicable to the battery of varying environment temperature and different degree of aging.

Accompanying drawing explanation

Fig. 1 a kind ofly eliminates the process flow diagram of low temperature on the method that energy-storage battery inner walkway affects;

Fig. 2 is coefficient κ ₁, κ ₂, κ ₃, κ ₄carry out the fitting effect curve map of matching.

Embodiment

Embodiment one: see figures.1.and.2 and illustrate present embodiment, a kind of method eliminated low temperature and energy-storage battery inner walkway is affected described in present embodiment, the method is:

Step one: the functional equation setting up temperature variation and internal resistance variable quantity:

$\begin{array}{c}{\mathrm{\ΔR}}_o={\mathrm{\ΔR}}_{bulk}+{\mathrm{\ΔR}}_{SEI}+{\mathrm{\ΔR}}_{ct}\\ =k_{bulk}(T-T_{std})+k_{SEI}(T-T_{std})+k_{ct}(\frac{1}{e^{-E_a/(T+273)}}-\frac{1}{e^{-E_a/(T_{std}+273)}})\end{array}$

Wherein, Δ R _ofor energy-storage battery internal resistance variable quantity, Δ R _bulkfor the variable quantity of bulk resistor, Δ R _sEIfor the variable quantity of SEI resistance (solid electrolyte film resistance), Δ R _ctfor the variable quantity of charge transfer resistance, T is actual temperature, T _stdfor standard temperature, E _afor apparent activation energy, k _bulk, k _sEI, k _ctbe respectively the temperature coefficient of bulk resistor, SEI resistance, charge transfer resistance;

Carry out arranging to above formula and obtain the functional equation after arranging:

${\mathrm{\ΔR}}_o={\mathrm{\κ}}_{1}T+{\mathrm{\κ}}_2{e}^{{\mathrm{\κ}}_3/(T+273)}+{\mathrm{\κ}}_4$

Wherein, κ ₁for combined temperature coefficient, the κ of bulk resistor and SEI resistance ₂for the temperature coefficient of charge transfer resistance, κ ₃for energy of activation coefficient, κ ₄for the resnstance transformer coefficient under standard temperature;

Step 2: obtain different temperatures by experiment, the energy-storage battery internal resistance of different ageing step is subject to the variable quantity that temperature affects, and according to this variable quantity to coefficient κ ₁, κ ₂, κ ₃, κ ₄carry out matching, obtain the functional equation after matching;

Step 3: environment temperature is measured, and this ambient temperature measurement value is brought in the functional equation after the matching of step 2 acquisition, obtain the energy-storage battery internal resistance variable quantity caused by temperature variation, utilize this energy-storage battery internal resistance variable quantity to eliminate temperature to the impact of energy-storage battery internal resistance.

Due to internal resistance of cell R _oprimarily of the bulk resistor R of battery _bulk, solid electrolyte film resistance R _sEIwith charge transfer resistance R _ctthree parts are formed.Different resistance has different Variation Features for temperature.For bulk resistor and solid electrolyte film resistance, its variation with temperature presents linear variation relation, and the change variation with temperature for its resistance of charge transfer resistance then meets Arrhenius (Arrhenius) function.

So, present embodiment by set up battery temperature change and the internal resistance of cell change between corresponding relation, in conjunction with the measurement to experimental situation temperature, so elimination temperature the internal resistance of cell is tested to the impact caused.

Embodiment two: present embodiment is described further the method that energy-storage battery inner walkway affects a kind of low temperature of eliminating described in embodiment one, in present embodiment, standard temperature T _stdit is 30 DEG C.

Claims (2)

1. eliminate the method that low temperature affects energy-storage battery inner walkway, it is characterized in that, the method is:

Step one: the functional equation setting up temperature variation and internal resistance variable quantity:

$\begin{array}{c}{\mathrm{\ΔR}}_o={\mathrm{\ΔR}}_{bulk}+{\mathrm{\ΔR}}_{SEI}+{\mathrm{\ΔR}}_{ct}\\ =k_{bulk}(T-T_{std})+k_{SEI}(T-T_{std})+k_{ct}(\frac{1}{e^{-E_a/(T+273)}}-\frac{1}{e^{-E_a/(T_{std}+273)}})\end{array}$

Wherein, △ R _ofor energy-storage battery internal resistance variable quantity, △ R _bulkfor the variable quantity of bulk resistor, △ R _sEIfor the variable quantity of SEI resistance, △ R _ctfor the variable quantity of charge transfer resistance, T is actual temperature, T _stdfor standard temperature, E _afor apparent activation energy, k _bulk, k _sEI, k _ctbe respectively the temperature coefficient of bulk resistor, SEI resistance, charge transfer resistance;

Carry out arranging to above formula and obtain the functional equation after arranging:

${\mathrm{\ΔR}}_o={\mathrm{\κ}}_{1}T+K_2{e}^{{\mathrm{\κ}}_3/(T+273)}+{\mathrm{\κ}}_4$

Wherein, κ ₁for combined temperature coefficient, the κ of bulk resistor and SEI resistance ₂for the temperature coefficient of charge transfer resistance, κ ₃for energy of activation coefficient, κ ₄for the resnstance transformer coefficient under standard temperature;

Step 2: obtain different temperatures by experiment, the energy-storage battery internal resistance of different ageing step is subject to the variable quantity that temperature affects, and according to this variable quantity to coefficient κ ₁, κ ₂, κ ₃, κ ₄carry out matching, obtain the functional equation after matching;

Step 3: environment temperature is measured, and this ambient temperature measurement value is brought in the functional equation after the matching of step 2 acquisition, obtain the energy-storage battery internal resistance variable quantity caused by temperature variation, utilize this energy-storage battery internal resistance variable quantity to eliminate temperature to the impact of energy-storage battery internal resistance.

2. a kind of method eliminated low temperature and affect energy-storage battery inner walkway according to claim 1, is characterized in that, standard temperature T _stdit is 30 DEG C.