This document describes a PSpice model of a lithium-ion battery. It includes an open circuit voltage (OCV) table relating state of charge (SOC) to voltage. Simulation results show the battery voltage discharging over time at different time scales. Adjusting parameters like the E2 value and cycle factor impact the discharge curve. The model allows simulating charge/discharge cycles and effects of capacity fading over multiple cycles.

1. PSpice and LTspice model of a Lithium-Ion battery
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Concept of Device Modeling
(Version 1.0)
Bee Technologies Inc
http://www.bee-tech.info/

2. PSpice model of a Lithium-Ion battery
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OCV Table
• C, battery capacity in ampere-hours
• SOC=100, the initial state of charge = fully
• OCV, battery open circuit voltage
R1
GND
V1
Hi
IN-
OUT+
OUT-
IN+
G6
GVALUE
GND
C2
7
R2
IN-
OUT+
OUT-
IN+
G1
GVALUE
0
N
1
C1
0
IN+
IN-
OUT+
OUT-
E3
EVALUE
12
IN+
IN-
OUT+
OUT-
E2
EVALUE
0
3
VMAX
100
4
U1
ETABLE
2
R5
R4
GND
D1
D2
0
D3
9
SOC
PARAMETERS:
C = 1.4
Tscale = 3600
SOC = 100
C3
R3
OCV

3. 1.Simulation result (Tscale = 1, 3600)
Tscale=1 Tscale=3600
• Simulated result shows battery voltage discharging.
• C cell (1.4 amp / 1hr, 3.6V) Spec.
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Time
0s 1.0s 2.0s 3.0s 3.6s
V(Hi)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
Time
0s 10Ks 20Ks 30Ks 36Ks
V(Hi)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
Total job time (using Solver 1) = 0.27s, 10ms/step.Total job time (using Solver 1) = 649.34s, 10ms/step.

4. 1.Simulation result (Tscale = 1, 3600)
Tscale=1 Tscale=3600
• Simulated result shows battery voltage discharging.
• C cell (1.4 amp / 3600s, 3.6V) Spec.
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Time
0s 1.0s 2.0s 3.0s 3.6s
V(Hi)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
Time
0s 10Ks 20Ks 30Ks 36Ks
V(Hi)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
Total job time (using Solver 1) = 0.27s, 10ms/step.Total job time (using Solver 1) = 2.52s, 100s/step.

5. 2.OCV table = Electrochemical characteristics of Li-ion
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3
3.5
4
4.5
5
0 20 40 60 80 100
OCV[V]
SOC [%]
SOC(%) OCV(V)
1.03217 3.54396
5.60322 3.60771
10.1743 3.67558
16.2198 3.71877
24.6247 3.76401
29.3432 3.78252
36.7158 3.81131
44.6783 3.83393
52.9357 3.8545
59.866 3.87918
65.7641 3.89974
74.0214 3.94293
79.9196 3.97172
87.4397 4.03136
93.3378 4.08483
100.854 4.1671

6. 3.Simulation result (G6, Function)
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V(U1.G6:OUT+,U1.G6:OUT-)
0V 1.0V 2.0V 3.0V 4.0V
I(U1.G6)
0A
1.0A
2.0A
3.0A
4.0A

7. 4.Initial Voltage (Charge/Discharge)
Charge Discharge
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Time
0s 1.0s 2.0s 3.0s 4.0s
V(U1:Hi) V(U1.OCV)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
Time
0s 1.0s 2.0s 3.0s 4.0s
V(U1:Hi) V(U1.OCV)
0V
1.0V
2.0V
3.0V
4.0V
5.0V

8. 5. Discharge Cycle
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Value increase as
cycle time increase.
Value increase as
cycle time increase.
V1
Hi
IN-
OUT+
OUT-
IN+
G6
GVALUE
GND
C2
7
R2
IN-
OUT+
OUT-
IN+
G1
GVALUE
0
N
1
C1
0
IN+
IN-
OUT+
OUT-
E3
V(OCV)
EVALUE
R1
12
IN+
IN-
OUT+
OUT-
E2
EVALUE
0
GND
3
C3
VMAX
100
4
R3
{6.8/C}
U1
ETABLE
2
R5
R4
GND
D1
D2
0
D3
9
PARAMETERS:
C = 1.4
Tscale = 3600
SOC = 100
SOC
OCV

9. 5. Discharge Cycle
Charge Discharge
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Time
0s 1.0s 2.0s 3.0s 4.0s
V(Hi)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
Time
0s 1.0s 2.0s 3.0s 4.0s
V(Hi)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
cycle factor=1
cycle factor=2
cycle factor=1
cycle factor=2

10. 6. E2
Charge Discharge
• E2={0.5*exp(-V(SOC)/A)}
• A=10
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Time
0s 1.0s 2.0s 3.0s 4.0s
V(U1:Hi) V(U1.OCV)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
Time
0s 1.0s 2.0s 3.0s 4.0s
V(U1:Hi) V(U1.OCV)
0V
1.0V
2.0V
3.0V
4.0V
5.0V

11. 6. E2
Charge Discharge
• E2={0.5*exp(-V(SOC)/A)}
• A=20 [default]
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Time
0s 1.0s 2.0s 3.0s 4.0s
V(U1:Hi) V(U1.OCV)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
Time
0s 1.0s 2.0s 3.0s 4.0s
V(U1:Hi) V(U1.OCV)
0V
1.0V
2.0V
3.0V
4.0V
5.0V

12. 6. E2
Charge Discharge
• E2={0.5*exp(-V(SOC)/A)}
• A=40
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Time
0s 1.0s 2.0s 3.0s 4.0s
V(U1:Hi) V(U1.OCV)
0V
1.0V
2.0V
3.0V
4.0V
5.0V
Time
0s 1.0s 2.0s 3.0s 4.0s
V(U1:Hi) V(U1.OCV)
0V
1.0V
2.0V
3.0V
4.0V
5.0V

13. V(U1.SOC)@1
0V 20V 40V 60V 80V 100V
V(U1.N)
0V
100mV
200mV
300mV
400mV
500mV
6. E2
• {0.5*exp(-V(SOC)/A)}
• List: 10, 20, 40
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A=10 A=20 A=40