Datasheet Battery

Lithium-ion, lithium-polymer, or lead-acid battery

• Library:

• Powertrain Blockset / Energy Storage and Auxiliary Drive / Datasheet Battery

• 

Description

The Datasheet Battery block implements a lithium-ion, lithium-polymer, or lead-acid battery that you can parameterize using manufacturer data. To create the open-circuit voltage and internal resistance parameters that you need for the block, use the manufacturer discharge characteristics by temperature data. For an example, see Generate Parameter Data for Datasheet Battery Block.

To determine the battery output voltage, the block uses lookup tables for the battery open-circuit voltage and the internal resistance. The lookup tables are functions of the state-of charge (SOC) and battery temperature, characterizing the battery performance at various operating points:

$$\begin{array}{l}{E}_m=f(SOC)\\ R_{int}=f(T,SOC)\end{array}$$

To calculate the voltage, the block implements these equations.

$$\begin{array}{l}{V}_T=E_m+I_{batt}{R}_{int}\\ I_{batt}=\frac{I_{in}}{N_p}\\ V_{out}=\{\begin{array}{c}{N}_s{V}_T\text{ unfiltered}\\ \frac{V_{out}}{\tau s+1}\text{ filtered}\end{array}\\ SOC=\frac{1}{Ca{p}_{batt}}{\displaystyle \underset{0}{\overset{t}{\int }}{I}_{batt}}dt\\ L{d}_{AmpHr}={\displaystyle \underset{0}{\overset{t}{\int }}{I}_{batt}}dt\end{array}$$

Positive current indicates battery discharge. Negative current indicates battery charge.

Power Accounting

For the power accounting, the block implements these equations.

Bus Signal			Description	Equations
PwrInfo	PwrTrnsfrd — Power transferred between blocks Positive signals indicate flow into block Negative signals indicate flow out of block	PwrLdBatt	Battery network power	$\begin{array}{l}{V}_{batt}=V_{out}\text{ OR }\frac{V_{out}}{\tau s+1}\\ \\ P_{batt}=-V_{batt}{I}_{batt}\\ P_{LdBatt}= -P_{batt}\end{array}$
	PwrNotTrnsfrd — Power crossing the block boundary, but not transferred Positive signals indicate an input Negative signals indicate a loss	PwrLossBatt	Battery network power loss	$$P_{LossBatt}=-N_p{N}_s{I}_{batt}{}^2{R}_{int}$$
	PwrStored — Stored energy rate of change Positive signals indicate an increase Negative signals indicate a decrease	PwrStoredBatt	Battery network power stored	$P_{StoredBatt}=P_{Batt}+P_{LossBatt}$

The equations use these variables.

SOC	State-of-charge
Em	Battery open-circuit voltage
Ibatt	Per module battery current
PLdBatt	Battery network power
Pbatt	Battery power
PLossBatt	Battery network power loss
PStoredBatt	Battery network power stored
Iin	Combined current flowing from the battery network
Rint	Battery internal resistance
Ns	Number of cells in series
Np	Number of cells in parallel
Vout, Vbatt	Combined voltage of the battery network
VT	Per module battery voltage
Capbatt	Battery capacity
LdAmpHr	Battery energy

Ports

Inputs

CapInit — Battery capacity

scalar

Rated battery capacity at the nominal temperature, Cap_batt, in Ah.

Dependencies

To create this port, select External Input for the Initial battery capacity parameter.

BattCurr — Battery load current

scalar

Combined current flowing from the battery network, I_in, in A.

BattTemp — Battery temperature

scalar

Temperature measured at the battery housing, T, in K.

Output

Info — Bus signal

bus

Bus signal containing these block calculations.

Signal			Description	Variable	Units
BattCurr			Combined current flowing from the battery network	Ibatt	A
BattAmpHr			Battery energy	LdAmpHr	A*h
BattSoc			State-of-charge capacity	SOC	NA
BattVolt			Combined voltage of the battery network	Vout	V
BattPwr			Battery network power	Pbatt	W
PwrInfo	PwrTrnsfrd	PwrLdBatt	Battery network power	PLdBatt	W
	PwrNotTrnsfrd	PwrLossBatt	Battery network power loss	PLossBatt	W
	PwrStored	PwrStoredBatt	Battery network power stored	PStoredBatt	W

BattVolt — Battery output voltage

scalar

Combined voltage of the battery network, V_out, in V.

Parameters

Block Options

Initial battery capacity — Input or parameter

Parameter (default) | External Input

Initial battery capacity, Cap_batt, in Ah.

Dependencies

Block Parameter Initial battery capacity Option	Creates
External Input	Input port CapInit
Parameter	Parameter Initial battery capacity, BattCapInit

Output battery voltage — Unfiltered or Filter

Unfiltered (default) | Filtered

Select Filtered to apply a first-order filter to the output batter voltage.

Dependencies

Setting Output battery voltage parameter to Filtered creates these parameters:

• Output battery voltage time constant, Tc

• Output battery voltage initial value, Vinit

Rated capacity at nominal temperature, BattChargeMax — Constant

100 (default) | scalar

Rated battery capacity at the nominal temperature, in Ah.

Open circuit voltage table data, Em — 1-D lookup table

1-by-P matrix

Open-circuit voltage data curve, E_m, as a function of the discharged capacity for P operating points, in V.

Open circuit voltage breakpoints 1, CapLUTBp — Breakpoints

1-by-P matrix

Discharge capacity breakpoints for P operating points, dimensionless.

Although this parameter is the same as the Battery capacity breakpoints 2, CapSOCBp parameter, the block uses unique parameters for calibration flexibility.

Internal resistance table data, RInt — 2-D lookup table

N-by-M matrix

Internal resistance map, R_int, as a function of N temperatures and M SOCs, in ohms.

Battery temperature breakpoints 1, BattTempBp — Breakpoints

[243.1 253.1 263.1 273.1 283.1 298.1 313.1] (default) | 1-by-N matrix

Battery temperature breakpoints for N temperatures, in K.

Battery capacity breakpoints 2, CapSOCBp — Breakpoints

[0 0.2 0.4 0.6 0.8 1] (default) | 1-by-M matrix

Battery capacity breakpoints for M SOCs, dimensionless.

Although this parameter is the same as the Open circuit voltage breakpoints 1, CapLUTBp parameter, the block uses unique parameters for calibration flexibility.

Number of cells in series, Ns — Integer

1 (default) | scalar

Number of cells in series, dimensionless, N_s.

Number of cells in parallel, Np — Integer

1 (default) | scalar

Number of cells in parallel, dimensionless, N_p.

Initial battery capacity, BattCapInit — Capacity

100 (default) | scalar

Initial battery capacity, Cap_batt, in Ah.

Dependencies

Block Parameter Initial battery capacity Option	Creates
External Input	Input port CapInit
Parameter	Parameter Initial battery capacity, BattCapInit

Output battery voltage time constant, Tc — Filter time constant

1/1000 (default) | scalar

Output battery voltage time constant, T_c, in s. Used in a first-order voltage filter.

Dependencies

Setting Output battery voltage parameter to Filtered creates these parameters:

• Output battery voltage time constant, Tc

• Output battery voltage initial value, Vinit

Output battery voltage initial value — Filter initial voltage

4.221 (default) | scalar

Output battery voltage initial value, V_init, in V. Used in a first-order voltage filter.

Dependencies

Setting Output battery voltage parameter to Filtered creates these parameters:

• Output battery voltage time constant, Tc

• Output battery voltage initial value, Vinit

Model Examples

EV Reference Application

Simulate an EV model with a motor-generator, battery, direct-drive transmission, and associated powertrain control algorithms. Use the for powertrain matching analysis and component selection, control and diagnostic algorithm design, and hardware-in-the-loop (HIL) testing.

References

[1] Arrhenius, S.A. “Über die Dissociationswärme und den Einflusß der Temperatur auf den Dissociationsgrad der Elektrolyte.” Journal of Physical Chemistry. 4 (1889): 96–116.

[2] Connors, K. Chemical Kinetics. New York: VCH Publishers, 1990.

[3] Ji, Yan, Yancheng Zhang, and Chao-Yang Wang. Journal of the Electrochemical Society. Volume 160, Issue 4 (2013), A636-A649.

Extended Capabilities

C/C++ Code Generation
Generate C and C++ code using Simulink® Coder™.