This presentation overviews the work currently being done in Dr. Ted Yu's battery research lab at CSU Long Beach.

1. THE OPTIMIZATION OF
ELECTROLYTES FOR USE IN
BIOABSORABLE SODIUM-ION
BATTERIES
BY D. WALKER, E. THAI, T. HIGGWE, AND T. H.
YU
DEPARTMENT OF CHEMICAL ENGINEERING
CALIFORNIA STATE UNIVERSITY, LONG BEACH

2. ABSORBABLE BIOSENSERS
How Do We Power It?

3. DISSOLVABLE BATTERY
Mg- Mo stacked cell dissolves in water over the span of 24 days, viewed
clockwise starting from upper right.
Rogers et al. Materials, Designs, and Operational Characteristics for Fully
biodegradable Primary Batteries. Adv. Mater. 2014, DOI:

4. DEPLOYMENT OF SODIUM BATTERY IN THE
BODY
• Edible and well below the
recommended daily amount.
2400mg for sodium and 11mg
for manganese.
• Recommended daily amount of
lithium is 3.42 mg
• Electrode made of polymer,
made with all naturally
occurring materials found in
most foods, and silver
nanowires
Bettinger et al. Self-deployable current sources
fabricated from edible materials. J. Mater. Chem. B,
2013, 1, 3781

5. CURRENT PROBLEM
• Electrolytes currently being used in lithium-ion batteries
(LIB’s) aren’t adequate for use in sodium-ion batteries
(SIB’s)
• We can use LIB electrolytes as a starting point for an
optimal SIB electrolyte

6. WHAT DOES A BATTERY CONSIST OF?
• Cathode
– Where electron is accepted (reduction)
• Anode
– Where electron is donated (oxidation)
• Electrolyte
– The medium in which ions can flow
• Separator
– Keeps the cathode and anode from directly reacting

7. BATTERY FABRICATION
• Everything is transferred into argon-filled glovebox
• All of the parts are stacked on top of one another
• Put into a crimping machine where 50 psi is applied to seal th

8. MATERIALS AND METHODS
Solvent Salt Additive Results
EC/DEC/EMC NaClO4 N/A - ±4 V
EC/DMC NaClO4 N/A - ±0.5 V
EC/PC/DMC NaClO4 N/A -starts ±0.5 V
-ends +1 & -2 V
EC/PC/DEC NaClO4 N/A -starts ±1 V
-ends -0.3 V
EC/PC NaClO4 N/A -starts ±0.2 V
-ends ±0.4 V
PC NaClO4 N/A -starts ±1.5 V
-ends ±2 V
EC/PC/DEC NaClO4 LiNO3 -voltage range differs
greatly b/t cycles
EC/PC/DEC NaTFSI N/A - ±5 V
EC/PC NaClO4 LiNO3 - ±2 V
• Cycle
symmetric
Na-Na Cells
• Ohms Law
• 0.5 mA
• ↑ V= ↑
Resistance

9. MATERIALS AND METHODS
Salt [Salt] (M) EC:PC
Ratio
NaClO4 1.2 3:7
7:3
6:4
1:1
2 3:7
7:3
6:4
1:1
Salt [Salt] (M) EC:PC
Ratio
NaPF6 1.2 3:7
7:3
6:4
1:1
2 3:7
7:3
6:4
1:1
Goal: Produce overpotential of ±0.05 V

10. MATERIALS AND METHODS
• Galvanostatic Cycling at 0.5 mA and Potentiostatic Impedance
Neware BTS3000 Bio-Logic SP-300

11. GALVANOSTATIC CYCLING RESULTS
Time vs. Voltage graph of a symmetrical sodium cell with EC/PC/NaClO4 (7:3)
ran at a constant current of ±0.5 mA
Neware BTS3000 Battery Tester

12. GALVANOSTATIC CYCLING RESULTS
Time vs. Voltage graph from galvanostatic cycling ran at +0.5 mA
Bio-Logic SP300 Potentiostat

13. POTENTIOSTATIC EIS RESULTS
Nyquist Plot of Na-Na cell
Analyzed with Kramer-Kronig Method
• Model Fit
• Experiment

14. RESULTS
R1 = 1.501 Ohm
R2 = 1,881 Ohm
Q2 = 15.08e-6 F.s^(a -
1)
R3 = 1,308 Ohm
Q3 = 0.612 7e-3 F.s^(a
Double LayerSEI Electrolyte

15. DISCUSSION
• Solid Electrolyte Interface (SEI) and Double Layer
contributed the most to the overall resistance present
within the cell
• Circuit model may have caused a discrepancy in
resistance values
• Average overpotential of 0.1V

16. CONCLUSION
• EC/PC/NaClO4 with a 7:3 ratio and 1.2 M salt
concentration resulted in the minimum overpotential
of the electrolytes tested
• Batteries tested with the optimized electrolyte should
show much more stable charge/discharge cycles;
yielding higher specific capacities
• More work can be done on lessening the impact of the
double layer and SEI layer

17. FUTURE WORK
• Sulfur-Polyacrylonitrile (SPAN) – Sodium Batteries
Capacity vs. Voltage graph of an Na-S cell ran at 0.1 mA

18. ACKNOWLEDGEMENTS
• Dr. Ted Yu
Research reported in this publication was supported by
the National Institute of General Medical Sciences of the
National Institutes of Health under Award Number
RL5GM118978. The content is solely the responsibility
of the authors and does not necessarily represent the
official views of the National Institutes of Health.