In 1912, American physical chemist Gilbert Lewis began experimentation on a lithium-based battery designed to replace the nickel-cadmium battery that had dominated the portable equipment space for a number of years. The lightest of all chemical metals, lithium holds a tremendous amount of electrochemical potential due to its high energy density. However, the natural instability of the lithium metal proved to be problematic when the energy storage device underwent recharging. As a result, it was not until 1970 when the first lithium-ion batteries were commercialized for public use. The lithium-ion combination proved to be a more stable (despite having a lower energy) density than lithium alone. Over the past 25 years, scientists and manufacturers have released many different types of lithium-based batteries, each one with a slightly different chemical makeup to prevent battery complications while maximizing charge performance. The next two passages highlight past issues with lithium batteries as well as the problems that still hinder rechargeable battery performance today. 
Before diving into the controversy surrounding lithium batteries, it should be noted that these batteries are by and large very reliable and productive. However, as is the case with any energy storage device, breakdowns do happen and for the most part, these failures are the result of some short circuit within the charging cell. Dating back to the 1800s, steam engines routinely exploded due to boiler or furnace over-pressure and over-heating. In the early 20th century, automobiles frequently experienced fire outbreaks as a result of stored flammable gasoline. Though these incidents were not caused by lithium, the concept of creating a foolproof, safe energy storage mechanism has challenged engineers as more and more manufacturers opt to build their devices with rechargeable batteries. 
Most short circuit episodes can be traced back to the presence of external microscopic metal particles that come into contact with the other parts of the battery cell. Despite trying to limit the presence of these particles, battery cells with very thin separators (24 micrometers or smaller), are at risk for contamination of outside particles. Through iterations of recalls and experimentation, manufacturers have honed their focus on limiting design flaws mainly affecting three aspects of the battery: electrode, separator and electrolyte. 
The lithium battery overheating process generally begins with a collection of microscopic particles in one distinct spot, which gradually warms due to a current formed between the collection spot and the electrodes of the cell. In the event of a "thermal runaway", the temperature of the cell's insulation cover will reach 500°C, drastically increasing the risk for an explosion. During an overheating episode, it is best to move the lithium-ion battery away from any flammable materials and onto any non-combustible surface. 
In addition to the engineering flaws and accidents described above, many incidents involving lithium battery explosions can be attributed to management oversights. Numerous commercialized products with rechargeable batteries function fine at the outset, but overtime experience shorts due to the defected battery finally failing. In many cases, the contempt of manufacturers leads to the release of products that have flaws and are not ready for public use. Though defects with any product are to be expected, the history of issues with lithium batteries specifically is well documented and as a result, should be close to resolution.
© Kyle Weikert. The author grants permission to copy, distribute and display this work in unaltered form, with attribution to the author, for noncommercial purposes only. All other rights, including commercial rights, are reserved to the author.
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