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Neither the lithium anode nor the manganese cathode are pure substances. Having a battery with only pure substances would make batteries highly unstable and dangerous. This means that both the manganese and lithium are more complex molecules, for example many common lithium-ion batteries use layered oxides containing cobalt and nickel for the (The Minerals, Metals, and Materials Society). The full list of contents in most lithium-ion batteries are as follows (not including the casing materials):

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Cobalt

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Nickel

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Manganese

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Lithium

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Graphite

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Silicon

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Polymer electrolytes This list is for lithium-ion batteries that use a cobalt compound for the cathode. As mentioned previously, much of battery advancements have been in material studies and implications. Unfortunately, the materials of modern batteries do pose issues. Several of these materials have limited availability in nature and are toxic, specifically cobalt (The Minerals, Metals, and Materials Society). It is also important to note that the structure of the materials creates a huge impact upon the effectiveness of the battery. When creating a manganese cathode it is important to create nano-pores in the material so that the lithium-ions can interact with the manganese more fully. If the cathode is not porous then the surface area of which the lithium-ions may attach to is limited to the side of the cathode. With pores though, th e surface area becomes greatly increased. Think of the cathode like a sponge that is trying to absorb lithium-ions, a sponge with no holes would not be able to pick up much water just as a cathode with no pores would only be able to attract a small amount of lithium-ions. Excessive heat c an cause the materials in the battery, specifically the cathode, to deform over time (Martha et al.). This heat deformation is responsible for decreasing performance ability in batteries.

Energy Density of Batteries

Energy density refers to the ratio of charge to materials. Larger energy density means that the battery outputs more energy for the same amount of material by mass. For electric cars, a battery with high energy density means that the car can travel longer before it needs to be recharged. A gasoline powered car with a 15 gallon tank that gets 25 miles p er gallon can travel a total distance of 375 miles before it hits empty. Currently, the Tesla Model S can travel 265 miles before it needs to be recharged (US EPA). For some context, I can take a fully charged Model S and drive from Milwaukee to Chicago, Back to Milwaukee, and still have a third of a tank left. 265 miles is a fair range for short to medium length trips, but for current electric cars to be able to travel as far as traditional gasoline powered cars the energy density of the lithium-ion batteries need to see about a 40% increase in energy densit y (assuming no more lithium is to be used in the batteries). The following are several ideas that show promise for increased energy density:

Solid State Electrolyte