energy institute battery research group
DESCRIPTION
ENERGY INSTITUTE Battery Research Group. Analysis of Overcharge & Overdischarge Characteristics and Failure Detection of Li – ion Polymer Batteries Cem Kaypmaz 2008 İstanbul. Advanced Batteries. - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/1.jpg)
ENERGY INSTITUTEENERGY INSTITUTEBattery Research GroupBattery Research Group
Analysis of Overcharge & Overdischarge Characteristics and Failure Detection of Li – ion Polymer Batteries
Cem Kaypmaz
2008
İstanbul
![Page 2: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/2.jpg)
Advanced Batteries
Having a Battery Management System (BMS) integrated with cells is necessary and “State Deterimation”, is a critical issue.
• The in-situ characterization of a battery is an interest for the battery manufacturers, suppliers and the third party users.
• Independent from the battery chemistry either primary or secondary, batteries are designed to perform an application specific usage.
• Studies are focused on, Telecommunication, Aerospace, Advanced Electrified Vehicles (EV, HEV, PHEV) and most Military energy storage systems.
![Page 3: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/3.jpg)
Battery State : Aging ?
Ref: Jossen et al, 2005
![Page 4: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/4.jpg)
Battery State
State of Charge State of Health
Battery State
Reversible Changes Irreversible Changes
- Effective Capacity- Internal Resistance- Open Circut Voltage- Gas Production
![Page 5: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/5.jpg)
SoC State of Charge (SoC):
• (remaining capacity) / (capacity of fully charged battery)
• (Cn – Qb) / Cn
Cn: nominal capacity
Qb: net dicharged charge from a battery since the last SoC FULL
1 > SoC > 0
100% > SoC > 0%
![Page 6: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/6.jpg)
SoH State of Health (SoH):
• (measured capacity) / (rated capacity)
• Cm / Cn
Cm: measured capacityCn: nominal capacity
1 > SoH > 0As per definition, a battery is at its end of lifetime at SoH
of 0.8 . (Ref: Rand et al, 2004)
![Page 7: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/7.jpg)
SoF State of Function (SoF):
• Case variable
• User (or designer) defined
• May differ according to the operating conditions
![Page 8: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/8.jpg)
Failure Modes - I For many applications and battery types, failure modes of a
battery could be listed and summarized as follows:
• A certain loss of effective capacity loss of active material, loss of conductivity in active mass
• Increase in internal resistance resulting active power loss electrolyte loss,loss of active surface
![Page 9: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/9.jpg)
Failure Modes - II
• Increase in self discharge dendrites between the plates, poisoning of the electrolyte
• Internal short circuitformation of dendrites,
• Cell open circuit behavior grid corrosion, pasivation
![Page 10: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/10.jpg)
Battery State: Conventional...
State of Charge (SoC)
State of Health (SoH)
State of Function (SoF)
FailureSpace
OperationalArea
![Page 11: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/11.jpg)
Li- ion Polymer Cells
KOKAM SLPB 526495 Li-ion polymer Typical Capacity 3.3AhNominal Voltage 3.7V Life > 500cycles
(Ref: KOKAM data sheet, 2008)
4 cells : Cycling Tests
8 cells: Overcharge Tests
8 cells: Overdischarge Tests
![Page 12: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/12.jpg)
Experimental Setup
Battery Test System (Cycler)
8 channel,
20V, 3A
Frequency Analyser (P/G)
1 Mhz-10μHzs
10V, 20A power booster
![Page 13: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/13.jpg)
Impedance Spectroscopy
Changing the frequency of the excitation current gives the ability to detect different battery kinetics.
Ref: Barsoukov et al, 2005).
![Page 14: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/14.jpg)
The Model
• L: The inductive behavior (L) at high frequencies (4-5kHz)
• RΩ: Pure ohmic resistance of the cell (2-3 kHz)
• Rsei and Csei : The solid electrolyte interface (sei), a pasivation layer occurring on the anode (2kHz-20Hz)
• Rct and Cdl : the charge transfer resistance and the double layer capacity (2Hz-100mHz).
• ZW: Warburg Impedance, the diffusion behavior of the battery (50mHz to 5 mHz)
• EMF: is the direct voltage produced inside the battery (Gerschler et al, 2008).
L
Csei
RΩ
EMFRsei
Cdl
Rct
-
+ZW
![Page 15: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/15.jpg)
Tests The tests are planned to create abnormal conditions for the cells both in charge and discharge process. Normal operation voltage range of these cells declared by the manufacturer 2,7V – 4,2V and 3.3 Ah.
For “failure creation” these limits were passed and the cells were forced to failure.
• Overcharge Test (OCT) • Overdischarge Tests (ODT)
Also Cycling Tests (CT) was performed in order to follow up “normal” conditions and parameter changes.
![Page 16: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/16.jpg)
Test Procedures
Cycling Test Procedure Overdicharge Test Procedure
Overcharge Test Procedure
Balancing (OCT) Test Procedure
![Page 17: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/17.jpg)
Test Results After 40 Cycle Procedure
-5
0
5
10
15
15 20 25 30 35 40 45
Z re [mohm]
Z im
[m
oh
m]
ω
I
II
III
L
C1
R0
EMFR1
-
+ZW
![Page 18: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/18.jpg)
Test ResultsAfter 3 hours of Overcharge Procedure
-10
0
10
20
30
40
50
60
20 30 40 50 60 70 80 90 100 110 120
Z re [mohm]
Z i
m [
mo
hm
]
ω
I
II
III
IV
V
L
C1
R0
EMFR1
C2
R2
-
+ZW
![Page 19: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/19.jpg)
Test Results
Nyquist Plots for Different Test Procedures
-10
0
10
20
30
40
50
0 20 40 60 80 100 120 140
Z re [mohm]
Z im
[moh
m]
CT ODT OCT
ω
![Page 20: ENERGY INSTITUTE Battery Research Group](https://reader035.vdocuments.site/reader035/viewer/2022062409/56814ee6550346895dbc77ee/html5/thumbnails/20.jpg)
Acknowledgements