Battery
Battery Model.
Description
The Battery block is a simple battery model. You can also expose the charge output port and the thermal port of the battery.
To measure the internal battery charge level, under Main select the check box for Expose charge measurement port. This action displays an additional q port that outputs the current battery charge value. Use this functionality to change the load behaviour depending on the state of charge without the complexity of building a charge level meter.
To model the thermal effects of the battery, in the Thermal Port section, select the Thermal port checkbox. This action opens an additional H thermal port. If this mode is selected, additional parameters must be entered, in particular a second temperature must be set. For more information, see the Thermal Effects Modelling section.
The equivalent battery circuit consists of the fundamental battery model, self-discharge resistance , charge dynamics model and series resistance .
Battery model
If `Infinite' is selected for the Battery charge capacity parameter, the unit will model the battery as a series resistor and a constant voltage source. The charge level does not change over time.
If Finite
is selected for Battery charge capacity, the block models the battery as a series resistor and a charge-dependent voltage source. In this case, the voltage is a function of charge and has the following dependence:
where:
-
SOC (state of charge) is the ratio of the current charge to the nominal capacity of the battery.
-
- is the voltage when the battery is fully charged with no load (nominal voltage). It is set by the Nominal voltage parameter.
-
β is a coefficient that is calculated so that the battery voltage is V1 when the battery is charged AH1. Set the V1 voltage and AH1 cell capacity using the block parameters. AH1 is the charge when the idle (open circuit) voltage is equal to V1 and V1 is less than the nominal voltage.
The equation defines an approximation of the relationship between voltage and remaining charge. This approximation reproduces the increasing rate of voltage drop at low values of charge and ensures that the battery voltage becomes zero when the charge level is zero. The advantage of this model is that it requires a small number of parameters that are readily available in most data sheets.
Modelling battery extinction
For battery models with a finite charge capacity, it is possible to model the degradation of battery performance as a function of the number of discharge cycles. This degradation is called battery extinction. To use it, select the Battery fade checkbox. This setting opens additional parameters in the Fade section.
The block implements battery fade by scaling certain battery parameter values, which you specify in the Main section, based on the number of completed discharge cycles. The block uses multipliers , and for the values of the Cell capacity (Ah rating), Internal resistance and Voltage V1 when charge is AH1 parameters, respectively. These multipliers in turn depend on the number of discharge cycles:
Where:
-
- is a multiplier for the rated capacity of the battery.
-
- multiplier for the series resistance of the battery.
-
- multiplier for voltage V1.
-
- number of discharge cycles performed.
-
- number of complete discharge cycles completed before the start of the simulation.
-
- the nominal capacity of the battery in ampere hours.
-
- the instantaneous output current of the battery.
-
- Heaviside ("step") function for the instantaneous battery output current. This function returns
0
if the argument is negative and1
if the argument is positive.
The block calculates the coefficients k1, k2, and k3 by substituting the parameter values specified in Fade into these battery equations. For example, the block parameter set by default corresponds to the following coefficient values:
You can also define a starting point for modelling based on previous charge-discharge history using the high-priority variable Discharge cycles.
Modelling thermal effects
If the Thermal port parameter is checked, you must set additional parameters at the second temperature to determine the behaviour of the battery. The extended equations for the voltage when you set the thermal port are as follows:
Where:
-
- is the temperature of the battery.
-
- is the nominal temperature of the measurement.
-
- coefficient of temperature dependence of the parameter for .
-
.
-
- parameter-temperature dependence coefficient for β.
-
- is calculated as described in Battery Model using the temperature modified nominal voltage .
Internal series resistance, self-discharge resistance, and any charge-dynamic resistances are also functions of temperature:
where is the coefficient of dependence of the parameter on temperature.
All temperature dependence coefficients are determined from the corresponding values you enter for the nominal and second measurement temperature. If charge dynamics is included in the model, the time constants vary with temperature in a similar way.
The battery temperature is determined by summing all ohmic losses included in the model:
where:
-
- is the thermal mass of the battery.
-
- corresponds to the _i_th ohmic loss member. Depending on the configuration of the unit, the losses can be as follows:
-
Series resistance
-
Self-discharge resistance
-
First segment of charge dynamics
-
Second segment of charge dynamics
-
Third segment of charge dynamics
-
Fourth segment of charge dynamics
-
Fifth segment of charge dynamics
-
-
- voltage drop on the i-th resistance.
-
- is the _i_th resistance.
Charge dynamics modelling
You can simulate the battery charge dynamics using the Charge dynamics parameter:
-
No dynamics
- the equivalent circuit contains no parallel RC sections. There is no delay between the contact voltage and the internal battery charge voltage. -
One time-constant dynamics
- the equivalent circuit contains one parallel RC section. Specify the time constant using the First time constant parameter. -
Two time-constant dynamics
- the equivalent circuit contains two parallel RC sections. Specify the time constants using First time constant and Second time constant. -
Three time-constant dynamics
- the equivalent circuit contains three parallel RC sections. Set the time constants using First time constant, Second time constant and Third time constant. -
Four time-constant dynamics
- the equivalent circuit contains four parallel RC sections. Set the time constants using First time constant, Second time constant, Third time constant and Fourth time constant. -
Five time-constant dynamics
- the equivalent circuit contains five parallel RC sections. Specify the time constants using the parameters First time constant, Second time constant, Third time constant, Fourth time constant and Fifth time constant.
This figure shows the equivalent circuit for a unit configured with two time constant speakers.
In the schematic:
-
and are parallel RC resistors. Set these values using the First polarisation resistance and Second polarisation resistance parameters respectively.
-
and are parallel RC capacitances. The time constant τ for each parallel section relates the values of R and C using the relationship . Set the τ for each section using the parameters First time constant and Second time constant respectively.
-
- series resistance. Set this value using the Internal resistance parameter.
Modelling battery ageing
For battery models with a finite charge capacity, it is possible to simulate the deterioration that occurs when the battery is not in use. To do this, the Calendar aging parameter must be checked. Calendar aging affects both internal resistance and capacity. In particular, the increase in resistance depends on various mechanisms such as solid electrolyte interface (SEI) formation at the anode and cathode and current collector corrosion. These processes are mainly dependent on storage temperature, state of charge and time.
The Battery block applies calendar aging only during initialisation. When you select the Calendar aging checkbox, the Vector of time intervals parameter appears in the block settings, which stores the time intervals when the battery aged before the simulation started. Calendar aging during simulation is not covered by this parameter. |
This equation determines the increase in battery contact resistance as a result of calendar aging:
,
,
Where:
-
- Open-circuit voltage normalised to the nominal value. Parameter Normalised open-circuit voltage during storage, V/Vnom.
-
- Internal resistance. Parameter Internal resistance.
-
- time sample obtained from the Vector of time intervals parameter.
-
- A sample of temperatures obtained from the Vector of temperatures parameter.
-
- number of elements of the temperature sample.
-
b - linear scaling for voltage. Parameter Linear scaling for voltage, b.
-
c - constant offset for voltage. Parameter Constant offset for voltage, c.
-
d - temperature-dependent exponential increase. Parameter Temperature-dependent exponential increase, d.
-
a - time exponent. Parameter Time exponent, a.
-
q - electron charge, kl.
-
k - Boltzmann constant, J/K.
The R_age_multiplier
variable in the Data Inspector stores data on the calendar aging of the battery in the contacts with increasing resistance:
.
For block thermal modelling options, if you have set the Storage condition parameter to Fixed open-circuit voltage
, you must specify an additional parameter Open-circuit voltage measurement temperature to convert the open-circuit storage voltage to a temperature-independent state of charge during storage:
.
The open circuit voltage as a function of storage temperature is determined by this equation:
.
Finally, this equation defines the increase in resistance of the battery terminals due to calendar aging as a function of storage temperature:
.
Assumptions and limitations
-
The self-discharge resistance is assumed to be independent of the number of discharge cycles.
-
For the battery thermal modelling option, you provide attenuation data only for operation at the reference temperature. The unit applies the same multipliers , and to the parameter values corresponding to the second temperature.
-
When using the thermal block modelling options, use caution when operating at temperatures outside the temperature range limited by the Measurement temperature and Second measurement temperature parameter values. The unit uses linear interpolation for the coefficients of the derivative equations, and simulation results may become unphysical outside this range.
Ports
Output
SOC - battery level
scalar
Charge Level. Use this output port to change the load behaviour depending on the charge level without the complexity of building a charge value meter.
The level of charge is a normalised value equal to the ratio of the current charge to the nominal battery capacity . The unit estimates the current charge of the battery by integrating the output current of the battery terminals. To convert the state of charge to actual charge, you must use the correct rated battery capacity for each temperature.
Dependencies
To use this port, select the check box for the Expose charge measurement port parameter and set the Measurement output type parameter to SOC
.
q - current battery charge, Kl
scalar
Internal charge in coulombs. Use this output port to change the load behaviour as a function of charge, without resorting to the complexities of building a charge magnitude meter.
Dependencies
To use this port, select the Expose charge measurement port checkbox and set the Measurement output type parameter to `Charge in Coulombs'.
Non-directional
+ - positive contact
electricity
The electrical port associated with the positive contact of the battery.
- - negative contact
electricity
Electrical port associated with the negative contact of the battery.
H - battery heat port
heat
Thermal port connected to the battery thermal mass. When this port is activated, specify additional parameters to define the behaviour of the battery. For more information, refer to Modelling thermal effects.
Dependencies
To use this port, select the Thermal Port checkbox in the Thermal Port section.
Parameters
Main
Nominal voltage, Vnom - nominal output voltage of a fully charged battery
12 V (By default)
| positive number
The idle voltage of a fully charged battery.
Current directionality - current direction influence
Off (By default)
| On
If this checkbox is selected, the internal resistance will depend on the current direction.
Internal resistance - internal resistance of the battery
2 ohms (by default)
| positive number
.
Resistance of internal battery connections.
Dependencies
To use this parameter, uncheck Current directionality.
Internal resistance during charging - internal resistance of the battery during charging
2 ohms (by default)
| positive number
.
The internal resistance of the battery during the charging phase.
Dependencies
To use this parameter, select the Current directionality checkbox.
Internal resistance during discharging - internal resistance of the battery during discharging
2 ohms (by default)
| positive number
.
The internal resistance of the battery during the discharging phase.
Dependencies
To use this parameter, select the Current directionality checkbox.
Battery charge capacity - selects the battery model
Infinite (By default)
| Finite
.
Select one of the battery charge capacity modelling options:
-
Infinite
- battery voltage is independent of the charge received from the battery, infinite capacity. -
Finite
- battery voltage decreases as the charge decreases.
Cell capacity (Ah rating) - rated capacity of the battery at full charge
50 A*h (By default)
| Positive number
The maximum (nominal) battery charge in ampere hours. To set a target value for the initial battery charge at the start of the simulation, use the high-priority variable Charge.
Dependencies
To use this parameter, set the Battery charge capacity parameter to Finite
.
Voltage V1 when charge is AH1 - output voltage at charge level AH1
11.5 V (by default)
| positive number
.
The basic battery output voltage at AH1 charge level as specified in the parameter Charge AH1 when no-load voltage is V1. This parameter must be less than Nominal voltage, Vnom.
Dependencies
To use this parameter, set the Battery charge capacity parameter to Finite
.
Charge AH1 when no-load voltage is V1 - charge level when no-load output voltage is V1
25 A*h (by default)
| positive number
The battery charge level corresponding to the idle output voltage and set by Voltage V1 when charge is AH1.
Dependencies
To use this parameter, set the Battery charge capacity parameter to Finite
.
Self-discharge - select whether to simulate battery self-discharge.
Disabled (By default)
| On
If the checkbox is selected, the unit simulates battery self-discharge. The block simulates this effect as a resistor connected to the terminals of the fundamental battery model.
As the temperature increases, the self-discharge resistance decreases, resulting in an increase in self-discharge. If the resistance decreases too quickly, thermal discharge of the battery and numerical instability can occur. You can solve this problem by doing one of the following:
-
Reduce the thermal resistance.
-
Decrease the gradient of self-discharge resistance as a function of temperature.
-
Increase the self-discharge resistance.
Dependencies
To use this parameter, set the Battery charge capacity parameter to Finite
.
Self-discharge resistance is the resistance reflecting the self-discharge of the battery
2000 ohms (by default)
| positive number
.
The resistance in the fundamental battery model that reflects the self-discharge of the battery.
Dependencies
To use this parameter, tick the checkbox for Self-discharge.
Measurement temperature - the temperature at which the unit parameters are measured
298.15 K (by default)
| positive number
.
The T1 temperature at which the block parameters are measured in Main. For more information, see Modelling thermal effects.
Dependencies
To use this parameter, select the checkbox for Thermal Port.
Expose charge measurement port - whether or not to open the charge measurement port
Off (By default)
| On
Select the checkbox to open the charge measurement port and measure the internal battery charge level.
Measurement output type - select the signal in the measurement port
Charge in Coulombs (By default)
| SOC
The parameter has two values:
-
SOC
- the output receivesSOC
charge level values. -
Charge in Coulombs
- the output receives values of chargeq
in Coulombs.
Dependencies
This parameter is used if the Expose measurement port parameter is set to on
.
Dynamics
Charge dynamics - battery charge dynamics model
No dynamics (By default)
| One time-constant dynamics
| Two time-constant dynamics
| Three time-constant dynamics
| Four time-constant dynamics
| Five time-constant dynamics
Select how the battery charge dynamics are modelled. This parameter determines the number of parallel RC sections in the equivalent circuit:
-
No dynamics
- the equivalent circuit contains no parallel RC sections. There is no delay between the contact voltage and the internal battery charge voltage. -
One time-constant dynamics
- the equivalent circuit contains one parallel RC section. Specify the time constant using the First time constant parameter. -
Two time-constant dynamics
- the equivalent circuit contains two parallel RC sections. Specify the time constants using First time constant and Second time constant. -
Three time-constant dynamics
- the equivalent circuit contains three parallel RC sections. Set the time constants using First time constant, Second time constant and Third time constant. -
Four time-constant dynamics
- the equivalent circuit contains four parallel RC sections. Set the time constants using First time constant, Second time constant, Third time constant and Fourth time constant. -
Five time-constant dynamics
- the equivalent circuit contains five parallel RC sections. Specify the time constants using the parameters First time constant, Second time constant, Third time constant, Fourth time constant and Fifth time constant.
First polarisation resistance is the first RC resistance.
0.005 ohms (by default)
| positive number
.
The resistance of the first parallel RC section. This parameter primarily affects the ohmic losses of the RC section.
Dependencies
To use this parameter, set Charge dynamics to One time-constant dynamics
, Two time-constant dynamics
, Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
First time constant is the first RC time constant
30 s (by default)
| `positive number
The time constant of the first parallel RC section. This value is equal to R*C and affects the dynamics of the RC section.
Dependencies
To use this parameter, set Charge dynamics to One time-constant dynamics
, Two time-constant dynamics
, Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Second polarisation resistance - second RC resistance
0.005 ohms (by default)
| positive number
.
The resistance of the second parallel RC section. This parameter primarily affects the ohmic losses of the RC section.
Dependencies
To use this parameter, set Charge dynamics to Two time-constant dynamics
, Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Second time constant - second RC time constant
30 s (by default)
| positive number
The time constant of the second parallel RC section. This value is equal to R*C and affects the dynamics of the RC section.
Dependencies
To use this parameter, set Charge dynamics to Two time-constant dynamics
, Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Third polarisation resistance is the third RC resistance
0.005 ohms (by default)
| positive number
.
Resistance of the third parallel RC section. This parameter primarily affects the ohmic losses of the RC section.
Dependencies
To use this parameter, set Charge dynamics to Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Third time constant is the third RC time constant
30 s (by default)
| `positive number
The time constant of the third parallel RC section. This value is equal to R*C and affects the dynamics of the RC section.
Dependencies
To use this parameter, set Charge dynamics to Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Fourth polarisation resistance is the fourth RC resistance
0.005 ohms (by default)
| positive number
.
The resistance of the fourth parallel RC section. This parameter primarily affects the ohmic losses of the RC section.
Dependencies
To use this parameter, set Charge dynamics to Four time-constant dynamics
or Five time-constant dynamics
.
Fourth time constant - Fourth RC time constant
30 s (by default)
| positive number
.
The time constant of the fourth parallel RC section. This value is equal to R*C and affects the dynamics of the RC section.
Dependencies
To use this parameter, set the Charge dynamics parameter to Four time-constant dynamics
or Five time-constant dynamics
.
Fifth polarisation resistance - fifth RC resistance
0.005 ohms (by default)
| positive number
.
The resistance of the fifth parallel RC section. This parameter primarily affects the ohmic losses of the RC section.
Dependencies
To use this parameter, set Charge dynamics to Five time-constant dynamics
.
Fifth time constant is the fifth RC time constant
30 s (by default)
| positive number
.
The time constant of the fifth parallel RC section. This value is equal to R*C and affects the dynamics of the RC section.
Dependencies
To use this parameter, set Charge dynamics to Five time-constant dynamics
.
Fade
To use these parameters, set Battery charge capacity to Finite.
Battery fade - select whether or not to simulate battery degradation on charge and discharge
Off (By default)
| On
If checked, the unit simulates battery fade:
-
Disabled
- battery characteristics are independent of the number of charge-discharge cycles. -
on
- the battery characteristics change depending on the number of completed charge-discharge cycles. Selecting this option opens additional parameters in this section that define the battery characteristics after a certain number of discharge cycles. The unit uses the values of these parameters to calculate the scaling factors k1~, k2 and k3.
See Battery Fade Modelling for more information.
Number of discharge cycles, N - number of completed charge-discharge cycles
100 (By default)
| `positive number
The number of charge-discharge cycles after which the other parameters in this section are measured. It defines the scaling factors k1, k2 and k3 used in modelling battery extinction.
Dependencies
To use this parameter, select the check box for Battery fade.
Cell capacity after N discharge cycles - maximum battery capacity after N discharge cycles
45 A*h (by default)
| positive number
Maximum battery charge, in ampere-hours, after the number of discharge cycles specified by Number of discharge cycles, N.
Dependencies
To use this parameter, select the Battery fade checkbox.
Internal resistance after N discharge cycles - internal resistance of the battery after N discharge cycles
2.02 ohms (by default)
| positive number
.
The internal resistance of the battery after the number of discharge cycles specified by Number of discharge cycles, N.
Dependencies
To use this parameter, select the checkbox for Battery fade and uncheck the checkbox for Current Directionality under Main.
Average internal resistance after N discharge cycles - average internal resistance of the battery after N discharge cycles
2.02 ohms (by default)
| positive number
.
Average battery internal resistance on charge and discharge after the number of discharge cycles specified by Number of discharge cycles, N.
Dependencies
To use this parameter, select the Battery fade and Current Directionality check boxes under Main.
Voltage V1 at charge AH1 after N discharge cycles - output voltage at charge level AH1 after N discharge cycles
10.35 V (by default)
| positive number
.
Output voltage of the fundamental battery model at charge level AH1 after the number of discharge cycles specified by Number of discharge cycles, N.
Dependencies
To use this parameter, select the Battery fade checkbox.
Calendar Aging
To use these options, set Battery charge capacity to Finite.
Calendar aging - calendar aging capability
Disabled (By default)
| On
If the checkbox is selected, the unit uses calendar aging of the battery.
Storage condition - storage conditions
Fixed open-circuit voltage (by default)
| Fixed state of charge
.
Select the parameter that defines the state of charge during storage - open-circuit voltage or state of charge during storage.
Dependencies
To use this parameter, select the Calendar aging check box.
Normalised open-circuit voltage during storage, V/Vnom - normalised open-circuit voltage during storage
0.9 (By default)
| scalar
Normalised open-circuit voltage during storage.
Dependencies
To use this parameter, select the Calendar aging check box and set the Storage condition parameter to Fixed open-circuit voltage
.
Open-circuit measurement temperature - open-circuit temperature
298.15 K (by default)
| positive number
.
The temperature at which the open-circuit voltage measurements were taken.
Dependencies
To use this parameter, open the unit’s thermal port, select the checkbox for Calendar aging, and set Storage condition to `Fixed open-circuit voltage'.
State of charge during storage (%) - percentage state of charge during storage
50 (By default)
| positive number
State of charge during storage, in per cent.
Dependencies
To use this parameter, select the check box for Calendar aging and set Storage condition to `Fixed state of charge'.
Vector of time intervals - vector of time intervals
[0] (By default)
| `vector'.
Storage time intervals. This parameter must be equal in size to Vector of temperatures.
Dependencies
To use this parameter, select the check box for Calendar aging.
Vector of temperatures - storage temperatures
[273] K (by default)
| vector
Set of storage temperatures. This parameter must be equal in size to Vector of time intervals.
Dependencies
To use this parameter, select the check box for Calendar aging.
Linear scaling for voltage, b - linear scaling for voltage
2.2134e6 (By default)
| scalar
Linear scaling factor for open circuit voltage.
Dependencies
To use this parameter, select the check box for Calendar aging.
Constant offset for voltage, c - constant offset for voltage
1.632e6 (by default)
| scalar
Constant offset for open circuit voltage.
Dependencies
To use this parameter, select the check box for Calendar aging.
Temperature-dependent exponential increase, d - temperature-dependent exponential multiplier
0.515833569 (By default)
| scalar
Temperature-dependent exponential increase.
Dependencies
To use this parameter, select the checkbox for Calendar aging.
Time exponent, a - time exponent
0.75 (By default)
| scalar
The multiplier of the exponent that defines the time dependence.
Dependencies
To use this parameter, select the Calendar aging check box.
Temperature Dependence
To use these parameters, set Thermal port to On.
Nominal voltage at second measurement temperature - output voltage with fully charged battery
12 V (By default)
| `positive number
Idle voltage at second measurement temperature when the battery is fully charged.
Internal resistance at second measurement temperature - internal resistance of the battery
2.2 ohms (by default)
| positive number
.
Battery internal resistance at second measurement temperature.
Voltage V1 at second measurement temperature - output voltage at charge level AH1
11.4 V (by default)
| positive number
.
Output voltage of the main battery model at second measurement temperature and AH1 charge level set by the AH1 Charge at idle voltage V1 parameter.
Dependencies
To use this parameter, set Battery charge capacity to Finite.
Self-discharge resistance at second measurement temperature - resistance reflecting battery self-discharge
2200 ohms (by default)
| positive number
.
Resistance in the fundamental battery model at second measurement temperature reflecting battery self-discharge.
Dependencies
To use this parameter, select the checkbox for Self-discharge.
First polarisation resistance at second measurement temperature - first RC resistance at second measurement temperature
0.005 ohms (by default)
| positive number
.
Resistance of the first parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set Charge dynamics to One time-constant dynamics
, Two time-constant dynamics
, Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
First time constant at second measurement temperature - first RC time constant at second measurement temperature
30 s (by default)
| `positive number
Time constant of the first parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set Charge dynamics to One time-constant dynamics
, Two time-constant dynamics
, Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Second polarisation resistance at second measurement temperature - second RC resistance at second measurement temperature
0.005 ohms (by default)
| positive number
.
Resistance of the second parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set Charge dynamics to Two time-constant dynamics
, Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Second time constant at second measurement temperature - second RC time constant at second measurement temperature
30 s (by default)
| positive number
.
Time constant of the second parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set Charge dynamics to Two time-constant dynamics
, Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Third polarisation resistance at second measurement temperature - third RC resistance at second measurement temperature
0.005 ohms (by default)
| positive number
.
Resistance of the third parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set Charge dynamics to Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Third time constant at second measurement temperature - third RC time constant at second measurement temperature
30 s (by default)
| `positive number
Time constant of the third parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set Charge dynamics to Three time-constant dynamics
, Four time-constant dynamics
or Five time-constant dynamics
.
Fourth polarisation resistance at second measurement temperature - fourth RC resistance at second measurement temperature
0.005 ohms (by default)
| positive number
.
Resistance of the fourth parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set Charge dynamics to Four time-constant dynamics
or Five time-constant dynamics
.
Fourth time constant at second measurement temperature - Fourth RC time constant at second measurement temperature
30 s (by default)
| positive number
.
Time constant of the fourth parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set Charge dynamics to Four time-constant dynamics
or Five time-constant dynamics
.
Fifth polarisation resistance at second measurement temperature - fifth RC resistance at second measurement temperature
0.005 ohm (by default)
| positive number
.
Resistance of the fifth parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set the Charge dynamics parameter to Five time-constant dynamics
.
Fifth time constant at second measurement temperature - fifth RC time constant at second measurement temperature
30 s (by default)
| `positive number
Time constant of the fifth parallel RC section at second measurement temperature.
Dependencies
To use this parameter, set the Charge dynamics parameter to Five time-constant dynamics
.
Second measurement temperature is the temperature at which the unit parameters are measured
273.15 K (by default)
| positive number
.
The T2 temperature at which the unit parameters are measured in Temperature Dependence.
Thermal Port
Thermal port - enable thermal port
off (by default)
| on
Select this checkbox to enable the block thermal port and simulate battery thermal effects.
Thermal mass - the thermal mass associated with the thermal port
0000 J/K (by default)
| `positive number `
The thermal mass associated with the heat port is H. It represents the energy required to raise the temperature of the thermal port by one degree.
Dependencies
To use this parameter, select the checkbox for the Thermal port parameter.
Bibliography
-
Ramadass, P., B. Haran, R. E. White, and B. N. Popov. "Mathematical modelling of the capacity fade of Li-ion cells." Journal of Power Sources. 123 (2003), pp. 230-240.
-
Ning, G., B. Haran, and B. N. Popov. "Capacity fade study of lithium-ion batteries cycled at high discharge rates." Journal of Power Sources. 117 (2003), pp. 160-169.