Thin-film battery

Thin film lithium ion batteries are similar to conventional lithium-ion batteries, but they are composed of thinner materials, some only nanometers or micrometers thick, which allow the finished battery to be just millimeters thick. They have been developed primarily within the last decade. These batteries consist of a substrate, electrolyte, current collector, anode, cathode, and a separator. There has been much research into the determination of the most effective components for this type of battery. It has been shown recently that even ordinary printer paper can be used as a charge separator and a substrate. These thin film batteries are an improvement on the common secondary, or rechargeable, lithium ion batteries in some ways. The batteries exhibit the same voltage and current as their bulky counterparts, but their dimensions allow for making electronic devices like cell phones, laptops and even implantable medical devices smaller and also reduce the weight of portable battery powered devices because of their high energy density. These batteries can be formed into any shape and can be stacked, further reducing space.

Lithium-ion batteries are different from disposable lithium batteries in that they can be recharged. They have high energy density and last as long as other battery technologies. Inside the battery, positive lithium ions flow through the electrolyte from the anode to the cathode while the battery is being discharged. When recharging the battery, lithium ions move back to the anode. The Li-ion battery design is effective for supplying portable devices with larger power requirements. The modern mobile, technology-driven society relies on portable electronics with thinner power sources, and research into thin film batteries has increased to accommodate this demand.

Cathode materials in thin film lithium ion batteries are the same as in classical lithium ion batteries. They are normally metal oxides that are deposited as a film by various methods.

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