1. Screening and Analysis of Carbon additives used to improve DCA of Lead Acid Batteries
Presenter: Robert Hansen, Undergraduate, Department of Materials Science and Engineering
Co-Researcher: Shengyi Li, Graduate Student, Department of Materials Science and Engineering
Faculty Adviser, Dr. Benjamin Church, Department of Materials Science and Engineering

2. Introduction Lead Acid battery technology use is limited to SLI.
DCA of lead Acid Batteries is naturally poor.
Addition of Carbon additives can improve DCA properties
Carbon additives act as a catalyst to gas evolution.
Figure 1: PbSO4 Dis/Charge vs particle size

3. Methodology - Cyclic Voltammetry(CV)
Two electrode system
Micro Powder Electrode (working electrode)
Carbon additive is packed into the tip
50 µm2 electrode surface area.
Reference electrode
Mercury/Mercurous Sulfate (Hg/Hg2SO4, saturated K2SO4) design
Records current with respect to voltage
Electrodes hooked up to potentiostat and computer
Potential (voltage) Window: -1.8V to 1.9 Volts
Scan rate of: 20µV/s
5 cycles
Solution
H2SO4(aq) 1.28g/mL + Na2SO4(aq) 15g/L + PbO saturated.
Figure 2: Setup of CV test in Faraday cage.

4. Cyclic Voltammetry graph
Cathodic region:
Hydrogen evolution –greater the slope, more H2.
Peak - Reduction of O2 gas.
Anodic region:
Oxygen evolution – greater the slope, more O2.
Peak - Oxidation of H2 gas.
Missing information:
No peaks representing active materials
Peaks around point of hydrogen evolution
Anodic Region
Cathodic region
Figure 5: CV Cycle 5 for all plain carbon samples.

5. H2 evolution potential (V) O2 evolution potential (V)
Graphical Analysis
Sample
Cycle No.
H2 Slope
H2 evolution potential (V)
O2 Slope
O2 evolution potential (V)
Stability Window
PBX 31 1
-1.03E-06
-1.603
-2.26E-06
1.695
3.298 5
-9.19E-07
-1.468
-5.97E-07
1.796
3.264
BP45A111
-2.35E-05
-1.128
-2.27E-05
1.607
2.735
-2.55E-05
-1.246
-2.09E-05
1.497
2.743
PBX 51
-7.01E-05
-1.404
-7.76E-05
1.679
3.083
-7.29E-05
-1.255
-7.25E-05
1.562
2.817
PBX 51 MODA
-5.47E-05
-1.213
-3.90E-05
1.886
3.099
-7.51E-05
-1.323
-7.07E-05
1.587
2.91
PBX 51 MODB
-4.60E-05
-1.024 -
1.9
2.924
-3.58E-05
-1.476
-3.36E-05
1.77
3.246
PBX 51 MODB No PbO
-6.51E-05
-1.279
-5.58E-05
1.657
2.936
-6.57E-05
-1.28
-6.10E-05
1.557
2.837
PBX135
-2.04E-05
-1.093
-1.09E-05
1.868
2.961
-1.37E-05
-1.141
-2.03E-05
1.808
2.949

6. Conclusions Conclusions:
PBX 31 preformed the best in CV testing, primary candidate.
BP45A111 and PBX 135 performance was acceptable. Will be used in future stages of DCA project.
Methodology worked well for measuring the catalytic effects of carbon additives on electrolysis in a lead acid cell.
No oxidation or reduction peaks of active materials were present in CV results.

7. Re-evaluation of the electrode design!
Future Work
Re-evaluation of the electrode design!
Design - Electrode slurry spread onto lead foil
Feature a large surface area compared to micro electrode
Prototype negative plate for down the road.

8. Acknowledgments
Thankyou to Johnson Controls Inc. for providing materials and Lab space to conduct research. Additional funding provided by the Office of Undergraduate Research through the SURF Grant.

9. Thankyou for your time.

10. Bibliography
Hu, Jingcheng, Chengbin Wu, Xinle Wang, and Yonglang Guo. "Additives of Suppressing Hydrogen Evolution at Carbon-Containing Negative Plates of Valve-Regulated Lead-Acid Batteries." Int. J. Electrochem. Sci (2016): n. pag. Web. 4 Apr
Pavlov, Detchko. (2011). Lead-Acid Batteries - Science and Technology - A Handbook of Lead- Acid Battery Technology and its Influence on the Product. Elsevier.