Thursday

Christy Chan

Nanoscience Microscopy

UCLA

August 6, 2015

Thursday

For our presentation, I am in charge of the discussion about the current scientists and their approach to our question, what materials can be used to replace existing components in electrode? As my previous blog post stated, electrodes go through cycles of charging and discharging and they keep expanding and shrinking during each cycles. This leads to degrading of the battery. There are two current and recent experiments/researches that are being conducted in order to answer this question we proposed.

The first research was consist of utilizing super capacitor, which is a type of energy storage system. Instead of applying a chemical reaction like all other batteries, this is more of a static charge. The advantages of utilizing a super capacitor are that they can be charged extremely quick, have millions of cycle, and built with a long life. However, there is a disadvantage of it. The super capacitor hold only a small amount of energy from only about 2.5–2.7V, which makes it not useful.

Another research was formulated by Tsinghua and MIT University recently to improve the power and capacity of rechargeable batteries. The electrode is built like an egg with a shell and yolk. The electrode expands and shrinks the yolk, not harming the outside shell at all. The anode is made out of aluminum, instead of graphite like most batteries. Then, this research can improve battery life, power, and capacity. This research can lead us to our discovery and provide us insight to look into similar materials to improve battery life.

References:

https://newsoffice.mit.edu/2015/yolks-and-shells-improve-rechargeable-batteries-0805

http://batteryuniversity.com/learn/article/whats_the_role_of_the_supercapacitor

http://berc.berkeley.edu/storage-wars-batteries-vs-supercapacitors/

Wednesday

Christy Chan

Nanoscience Microscopy

UCLA
August 5, 2015

Wednesday

Many people own a phone in their lives or to be more specific 6.8 billion on this Earth. Another example is that over 2,405,518,376 people owned a computer. With this statistics, many would know that to power phones, computers, or any electronics, you would need batteries to do so. As time goes on, people would think that their phones or computers might be too outdated to function. This lead others to get an upgrade and waste money, not bothering to wonder about fixing the battery.

Then there comes the lithium ion batteries, one of the greatest advancement in technology especially for portable electronics, which is popular in our current and future generation. We are able to utilize wires to charge our electronics, instead of always changing the batteries built into our electronics. However, self-discharge and battery depletion starts to happen as time goes on. For example, many mobile phones are not expected to last longer than three years based on a study. Research, recently, has indicated that the materials and surfaces of the electrode correlates with their electrochemical performance. Therefore, this leads to the question if there are better materials that would improve the battery life for electronics. Many researches demonstrates that lithium metal can penetrate through separator and cause a contact between cathode and anode which leads to damages in the battery. Even though it has many advantages over many other metal anodes, there are still complications with it. During the late 1980s and 1990s, scientists made a breakthrough by substituting graphitic carbon for lithium metal, creating lithium ion batteries. However, all batteries still must come into depletion. So is there a better way to make more efficient batteries, meaning greater longevity and power?

References:

• http://qz.com/179897/more-people-around-the-world-have-cell-phones-than-ever-had-land-lines/
• http://www.sciencedirect.com/science/article/pii/S1293255805002852
• https://en.wikipedia.org/wiki/Lithium-ion_battery
• http://batteryuniversity.com/learn/article/how_to_prolong_lithium_based_batteries

        

Tuesday

Christy Chan

Nanoscience Microscopy

UCLA

August 4, 2015

Tuesday

Is cold fusion a possibility?

According to my previous blog post, fusion occurs in very high temperature. Such examples include supernova events. This, then, raises the questions if nuclear fusion can actually occur in room or cold temperature, not in super high temperature.

Cold fusion is defined as a nuclear reaction that slams small atoms to make larger atoms, occurring approximately at room temperature. Currently, there are no accepted model that cold fusion really happen. The closest to discovering the possibility of this happen in 1989 when these two scientists, Martin Fleischmann and Stanley Pons, believed that they observed cold fusion when they were performing electrolysis on deuterium water. Deuterium is an isotope of hydrogen since it has one extra number of neutrons. Nevertheless, palladium can absorb deuterium than hydrogen (with zero neutron). However, this idea of cold fusion was overturned as physicists found out the multiple errors and mistakes from Fleischmann’s and Pons’ discovery. Scientists tried to recreate it but the experimental replication was mostly impossible. Unfortunately, this ended the interest and hope in furthering the discovery of cold fusion. There are still scientists involved in trying to discover this process, but they are really few of them and barely any mainstream popularity. This creates the unanswered question of cold fusion which I would love to be able to know the answer. I would also love to know how it would be beneficial and damages to our human population. I also want to know that if it is damaging, then is there a way that we can make it less or not damaging in order to help mankind.

References:

• https://en.wikipedia.org/wiki/Cold_fusion#Criticism
• http://zeenews.india.com/news/sci-tech/cold-fusion-is-real-claim-scientists_1559235.html
• http://undsci.berkeley.edu/article/0_0_0/cold_fusion_science

Monday

Christy Chan

Nanoscience Microscopy

UCLA

August 3, 2015

Monday

I have always been interested in Chemistry and felt surprised that I understood the concept of it which lead me to take AP Chemistry to further my knowledge. I remembered a specific lesson in class which my teacher taught us the difference between nuclear fusion and fission. He explained the basic technicality of each of them. Nuclear fission is the splitting of large atoms such as U-235 or Pu-239 into smaller atoms with neutrons. Nuclear fusion is the slamming of small atoms/nuclei together to make larger energy and atoms. It fascinated my interest that there are such powerful reactions and creations that can happen with such small particles. One of the best usage of fusion involves creating a reactor combining fusion and fission to burn nuclear waste, which is happening in China currently. A somewhat bad usage/creation of it is nuclear weapons, which is generated by fission or both fission and fusion. A fusion reactor requires H-2 which is easy to obtain, produces a ton of energy, and creates no waste. However, this requires a tone of energy which means a super high temperature that is approximately up to 4x10^7 K. Another example of fusion is that elements are formed from the core of stars. Large stars release heavy elements generated during explosion into outer space in a supernova event. This adds on to the “hot” fusion since stars’ approximate surface temperatures ranges from 3,500K to 7,500K. This then creates the question for me if cold fusion  is a possibility.

References:

http://www.diffen.com/difference/Nuclear_Fission_vs_Nuclear_Fusion

https://en.wikipedia.org/wiki/Nuclear_weapon

http://chemwiki.ucdavis.edu/Physical_Chemistry/Nuclear_Chemistry/Fission_and_Fusion