Barrios Jaime “Batteries and Voltaic Cells”

“Batteries and Voltaic Cells”

Formal Honors Laboratory ProjectBy Jaime Barrios

Abstract

This is a brief analysis of the history and importance of the development of batteries focusing on electrochemical cells, especially in the Daniell cell. The purpose of the lab is to demonstrate the production of electrical current and voltage through a redox reaction in a Daniell cell. The experiment is tested using a virtual lab simulator where the data was collected and later analyzed to define a conclusion.

IntroductionIn modern age society, batteries have become an important factor in everyone’s lifestyle. But, how long has it been since batteries were discovered and became a necessity? While there is still controversy on when or who was the one to invent the first battery.

Evidence says that there has been evidence of battery-like artifacts in different parts of the words that range to be around 2000 years old (3). One of the dated to be made around 250 B.C. referred to as the “Baghdad Battery”. This artifact was thought to be used in gilding but contained similar component of a nowadays battery (1). However none of them influenced nor established a practical use for the future until hundreds of years later.

Fig 1. Baghdad Battery. A 2200 year old vessel may have been able to keep a charge.

Electrochemical cellsFrom the 17th to 18th century the ongoing investigation kept going nonstop on different explanations on how electricity worked but was not until Alessandro Volta made his breakthrough to become more practical. Otto von Guericke was one of the first scientists to wonder and test static charge build-up during the mid-1600s (4).

Fig 2. Otto von Guericke. (1602-1686)

Electrochemical cellsA couple of scientists made their work to be accumulated along with the observations of Luigi Galvani. Galvani was an Italian scientist who observed how living tissue behaved around an electrostatic generator and thunderstorms. These observations led him to believe that animals contained certain electricity (3)

Fig 3. Luigi Galvani. (1737 – 1798)

Electrochemical cellsHowever, Alessandro Volta, another Italian physicist managed to prove Galvani wrong in his explanations on what Volta elaborated to be a difference in potential mid two different metals (3). Volta was the first to consciously invent one of the earliest batteries to have a more practical value, the Voltaic Pile (7).

Fig 4. Alessandro Volta. (1745 – 1827)

Electrochemical cellsThe voltaic pile, also known as a voltaic cell, consisted of stacked discs of copper (Cu) and zinc (Zn) separated by an electrolyte (1). Nevertheless, it was both of their efforts from Galvani and Volta so this electrochemical cell is known as both galvanic cell and voltaic cell (4)

Fig 4. Voltaic Pile

Electrochemical cellsHowever, some problems came out of the voltaic pile that would later give John Frederic Daniell, a British chemist during 1836, to attempt to fix those details by discovering the Daniell cell by introducing more factors to the electrochemical cell (7).

Fig 5. John Frederich Daniell (1790 – 1845)

Purpose: The purpose of this lab is to study and observe the shifts in cell potential from a zinc sulfate solution and a copper (ll) sulfate solution while experimenting on different ranges of concentration.

Fig 6. Daniell cell diagram #1

Background

The daniell cell (a specific type of galvanic cell) depends on two half-reactions that act as a spontaneous redox reaction (4). This reaction consists of having a mixture of zinc and zinc ions in one container acting as an anode while having copper and copper ions inside a separate container (2). This is a basic setup connecting both sides by using an external wire from which the current of electrons, caused by the redox reaction, flows from anode to cathode (8). However, a charge imbalance is formed by having the anode (Zn) become slightly more positive, and the cathode (Cu) becoming slightly more negative.

Fig 6. Daniell cell diagram #2

Background

This is fixed by having a second component added to the system, a salt bridge (which consists of a concentrated, non reactive, electrolyte solution which in this case contains NaCl). It not only closes the circuit for the current to pass through and produce a voltage, but it balances the charge imbalance between both electrodes (2). Nevertheless, the salt bridge does not produce any chemical change on either solution (4).

Fig 6. Daniell cell diagram #3

Materials and MethodsTwo clean beakers were labeled as CuSO4 solution and the other as ZnSO4 solution. The mass for each solution was calculated to have 1 M concentration in 1 liter. A copper strip was cleaned using sandpaper and dipped into the copper sulfate solution and similarly, a zinc strip was cleaned the same way and dipped into the zinc sulfate solution. A salt bridge (containing NaCl) was used to connect the two solutions. Using a voltmeter and connecting wires, the negative terminal was wired to the zinc strip (anode) while the negative terminal was wired to the copper strip (cathode). The voltage pointed in the voltmeter was recorded. The same process was repeated in solutions with a variety of different concentrations for each solution.

Results and discussions

The purpose of this lab was to demonstrate the transference of electrons that created an electrical current through the process of oxidation and reduction in a chemical reaction and the real lab procedure was replaced by an online simulator procedure from which the data was collected to complete the analysis. While using the respectively same material was supposed to be used in the real lab, the results were recorded in table 1. The base concentration for each solution was 0.100 M giving a cell potential of 1.100 V. While keeping a constant concentration of ZnSO4 solution (anode) and decreasing the concentration of CuSO4 (cathode), the cell potential started increasing in voltage. When using a 0.0100 M concentration of CuSO4 solution (10% of its original value), the voltage reading resulted in a cell potential of 1.128 V (a total increment of 2.48% from its original value).

Results and discussions

This shows an inverse relationship between the cell potential and the concentration of the cathode. As the value in the concentration of the cathode decreases, the value of the cell potential increases. On the other hand, while using a constant value in the concentration of the CuSO4 (cathode) and decreasing the concentration of the ZnSo4 (anode), the cell potential started to decrease. When using a 0.0100 M concentration in a ZnSO4 solution, the voltage reading resulted in a cell potential of 1.072 V (an equal decrement of 2.48% from its original value). This data shows a direct relationship between the cell potential and the concentration of the anode. As the value of the anode’s concentration decreases, so does the cell potential.

The concentration

of ZnSO4 solution

(M)

The concentration

of CuSO4 solution

(M)

EMF of

the Cell

(V)

.100 0.100 1.100

.100 0.0500 1.108

.100 0.0200 1.120

.100 0.0100 1.128

0.500 .10 1.092

0.0200 .10 1.080

0.0100 .10 1.072

Table 1. The electromotive force on

different concentrations of ZnSO4 and

CuSO4

Conclusion

The experiment was a success to support the fact that a redox reaction as in a Daniell cell (or any voltaic cell) can cause a flow of electrons and therefore create a voltage. Even though this data is based only in a theoretical virtual lab, this is not the only experiment ever taken, but this process has also been used on a smaller scale with more powerful reactants while making batteries. While batteries also use two compounds of different chemical potentials, they do not have much space inside a battery so both metals are separated by the usage of an insulator and connected by an electrolyte where the electrons move in order to complete the same process as shown in the prior experiment. However, the chemical potential energy is stored until the energy moves through the device that needs electricity to work (1).

Conclusion

Lithium batteries have been one of the most used batteries in the early production of cars but also in the development of various aircraft systems and different electronic devices. However, the lithium battery has confronted difficulties and even issues where the battery can cause a fire (1). There have been improvements as the time has passed, but also developments to have different compounds to complement or replace the lithium inside the batteries. Some examples include the research that was done to create a Lithium-sulfur battery with an increase in performance and cyclability (6) or the sodium-ion batteries (SIBs) that has exceeded a high-performance (5). Both examples have shown potential for future developments that would not only change the battery market but lifestyle performances and what can possibly become a more electricity-based society than what has already become over time.

References

1. Alarco, J., & Talbot, P. (2015, April 30). The history and development of batteries. Retrieved March 12, 2020, from https://phys.org/news/2015-04-history-batteries.html

2. Ball, D. W., & Key, J. A. (2014, September 16). Applications of Redox Reactions: Voltaic Cells. Retrieved March 25, 2020, from https://opentextbc.ca/introductorychemistry/chapter/applications-of-redox-reactions-voltaic-cells-2/

3. Buchmann, I. (2019, June 14). BU-101: When Was the Battery Invented? Retrieved March 3, 2020, from https://batteryuniversity.com/learn/article/when_was_the_battery_invented

4. Determination of EMF of a Cell. (2015, December 14). Retrieved March 18, 2020, from https://amrita.olabs.edu.in/?sub=73&brch=8&sim=153&cnt=1

5. Jo, J. H., Jo, C.-H., Qiu, Z., Yashiro, H., Shi, L., Wang, Z., & Yuan, S. (2020). Nature-Derived Cellulose-Based Composite Separator for Sodium-Ion Batteries. Frontiers in Chemistry, NA. Retrieved March 18, 2020, from https://link-gale-com.ez2.maricopa.edu/apps/doc/A616956571/SCIC?u=mcc_smtn&sid=SCIC&xid=ae9b6ef5

References

6. Li, Y., Li, X., Hao, Y., Kakimov, A., Li, D., Sun, Q., & Kou, L. (2020). β-FeOOH Interlayer With Abundant Oxygen Vacancy Toward Boosting Catalytic Effect for Lithium-Sulfur Batteries. Frontiers in Chemistry, NA. Retrieved March 20, 2020, from https://link-gale-com.ez2.maricopa.edu/apps/doc/A621756751/SCIC?u=mcc_smtn&sid=SCIC&xid=317316f3

7. Pateli, I. M. (2017, October 5). Brief history of Electrochemistry. Retrieved March 18, 2020, from https://etn-socrates.eu/brief-history-of-electrochemistry/

8. Robinson, W. R. (n.d.). 17.2 Galvanic Cells. Retrieved March 12, 2020, from https://opentextbc.ca/chemistry/chapter/17-2-galvanic-cells