FROM THE DRAWING BOARD TO THE POWER IN OUR HAND?
A study of how the lithium-ion battery has affected our culture
Twenty-seven years ago, lithium-ion batteries came to the global market as a new Sony product. The creation of lithium-ion batteries came about rapidly and has continued to display remarkable progress in capacity, energy, power and cost reduction. These batteries were developed by the company Asahi Kasei. The master mind of the product was Yoshino Al Et who established the engineering principles of lithium-ion battery.
Cell phones, cars and other electronic devices have created an expanded need for portable power. The lithium-ion battery became an obvious solution as the science backing lithium-ion technology lept forward. The advancement of new materialsused for constructing lithium-ion batteries are presumed to continue to improve in all of its properties with new battery concepts in active materials, inert materials and cell designs. Initially, I wanted to look into the future of lithium-ion batteries and where they are going (TESLA TESLA TESLA) but then I started reading about lithium-ion batteries and their story and it’s interesting how a concept can make it’s from an idea’s in someone’s head to a billion systems spread around the world. Of course, this project isn’t the history of all battery cells but a brief look at the steps taken to get from the drawing board to the market.
Why are Lithium-Ion batteries important?
Among the many reasons the lithium ion batteries are so awesome, the reason they’re so widely used is due to their energy density. In a world where humans are continually trying to optimize the technology so that we could do more things in the same amount of space, density is the largest game. If lithium ion batteries are able to maximize energy density better than alkaline cell options then they are a more appropriate choice from an efficiency stand point and a cultural stand point.huh?
The beginning of the lithium-ion battery
Though Sony was the first primary producer and vendor of lithium-ion batteries, there were many pioneers that preclude the one sold in 1991. The concept of a cell in which the lithium ions move reversibly between the Anode and Cathode was first formulated by Armand in the late 1970s. The cell used intercalation materials of different potentials for the two electrodes. The design for this cell is often called a rocking chair battery because of the flow of lithium ions back and forward between the two electrodes.1 The design was picked up by Lazzari and Scrosati soon after and implemented with a lithiated tungsten dioxide electrode and a titanium disulfide electrode.
point The potential voltage range was only between 0.8 to 2.1 volts and the electrodes both featured significant molecular masses, but the principle was established. After the cell cycled for over 60 cycles, however, the charge voltage required was about 2.2 V and discharge was approximately a low return of 1.6 V.
A US labratory, Goodenough financed by ? and located in city,state, was working on research and development of batteries. Goodenough laboratory discovered the ability of NaFeO2 from the lithiated transition metal oxide family. The compound was able to both deintercalate and reintercalate lithium ions at relatively large potentials. Nickel and cobalt as well as other combinations with Mn, Al, Fe, were all found to have this ability and the later adoption of this patented material (LiCoO2) formed the active positive material of Sony’s lithium-ion battery.
Shortly after this technological advancement by, J. C. Hunter of the Eveready Laboratories were made. This research group discovered a new structure of MnO2, that could be reversibly reduced and oxidized in a nonaqueous electrolyte at a high potential similar to that of LiCoO2 with a similar capacity. The finding of this compound was so groundbreaking that it is still used to this day for applications that require higher rate batteries (e.g. portable weedwackers).
The discovery of suitable negative electrode materials was somewhat more complicated than finding new positive electrode materials. Early work on graphite and carbonaceous materials had shown that lithium ions could be intercalated. Yoshino and coworkers, from Asahi Kasei (a Japanese battery supplier of separators and electrolytes), used petroleum coke in a patent that resulted in identifying Yoshino as the original inventor of the lithium-ion battery.
The issue was that the reversible capacities of the cokes cycled at low rates which were only half that of the graphite. Yoshino decided to experiment with pure starting materials, rather than refined petroleum. The purity of the coke was much higher than those used by other laboratory groups. Many parties contributed to the evolution of the ion battery but Yoshino’s model was clearly a superior due to his more precise and mixtures of specific chemicals salt, binding and electrode combinations. Asahi Kasei later formed a joint venture to create A&T Battery Corp. to make lithium-ion batteries for retail.
Ion batteries go corporate
While the main elements of a lithium-ion battery were laid out by Yoshino, the battery was nowhere near ready for commercial applications compared to nickel cadmium and newly discovered nickel metal hydride batteries. The deficiencies of earlier alkaline batteries included low specific energy, poor charge retention and environmental problems with the cadmium system. This left the tech industry searching a better solution. Additionally, the electronics industry was rapidly developing, particularly in the sections of computations, communication and cameras. Sony was one of the leading companies in consumer electronics and was willing to bring new inventive products to the table unlike anything else on the market. Sony was a relative newcomer to the battery business.Sony severed that focus and began work in earnest on rechargeable batteries.1
The new generation of Cathode were introduced; a hard carbon with higher specific capacity was substituted for the coke. A still later development was the now commonly used mesophase carbon microbeads (MCMB). This gave a still higher specific capacity and a flat discharge profile. The positive electrode material, LiCoO2, was carefully designed to have a coarser particle size and good crystallinity.
A crash project with Kureha Chemical Ind. Co. developed an improved material giving greatly improved adhesion to the Al carrier foil. Sony’s role in producing magnetic tape was helpful in manufacturing the coated electrodes and there is no doubt that part of this experience involved the use of excellent production coating machinery, but, as confirmed by Toru Nagaura,1 one of the key engineers on the project, the particular kind of high energy mixing of the coating slurry was also of great importance. This was also around the time where Nickel coated iron cans were integrated into the system. Nickel coated iron cans were critical to the success of the project because stainless cans originally selected because of the presence of trace amounts of HF was found to have too high resistance for the applications envisioned.
Sony’s final product
The cell size selected was 18650. This number is based on the naming system for cylindrical lithium primary cells. The first two numbers represent the diameter in mm and the remaining numbers represent the height of the cell in tenths of mm – thus the common a 18650 cell is 18 mm diameter and 65 mm in height. This is the common size of AA batteries.
These dimensions were chosen because it was close to the volume of subC rechargeable nickel-based batteries which is still the most popular size for small electronic devices. The separator selected was a biaxially stretched microporous polyethene material. The electrolyte chosen was ethylene carbonate with a linear dialkyl carbonate and the salt was LiPF6 of high purity and state of dryness. The all-carbonate solvent has the important property of high oxidation resistance. Subsequent improvements in electrolyte have primarily involved the use of additives to improve the film on the negative materials and improve the oxidation stability of electrolyte to the positive active material.
The original Sony battery with coke negative had roughly 20 percent of the energy density of today’s batteries. The innovations of engineers have created solutions for longer lasting battery life, fewer battery recharges, and the refining of core electrodes, separators and containers. This has allowed us to exponentially grow the number of recycles batteries can undergo before loosing memory.
Sony remained the industry leader for some time. Eventually competition from many other producers led Sony towards a planned withdrawal from the battery market. Sony and Yoshino have left a mark on the world of transportable power that we live in today. Today we live in the echo of these engineers and developers.
1. Blomgren, George E.. “The Development and Future of Lithium Ion Batteries.” jes.ecsdl.org. Journal of The Electrochemical Society, 164, 1 Dec. 2016. Web. 25 Jan. 2018.
2. Thomas Waldmann, Jason B. Quinn, Karsten Richter, Michael Kasper, Alexander Tost, Andreas Klein, Margret Wohlfahrt-Mehrens, Electrochemical, Post-Mortem, and ARC Analysis of Li-Ion Cell Safety in Second-Life Applications, Journal of The Electrochemical Society, 2017, 164, 13, A3154
3. M. S. Whittingham, “Lithium Batteries and Cathode Materials”, Chem. Reviews, 104, 4271 (2004).