The Art of Energy

While deciding an optimal Lithium-ion cell chemistry for different applications, I came across this question quite a few times, ' Why different Li-ion cell chemistries have different terminal voltages? ' There are numerous LiB chemistry types available in the market. e.g. Lithium Cobalt Oxide (LCO), Li Nickel Cobalt Aluminum Oxide (NCA), Lithium Tantalate Oxide (LTO), Lithium Iron Phosphate (LFP), etc to name a few. However, each and every battery type has its positive-negative points. Although the working principle of all these chemistries is the same, their terminal voltages are different. For example, LCO cells can go up to 4.25V, NCA can be charged up to 4.2V whereas LFP and LTO type cells can have a maximum of 3.8V and ~2.5V respectively. This difference in the voltage has a very large effect on the battery capacity (since energy capacity is directly proportional to the battery voltage). In this blog, I will answer 'Why different LiB chemistries have different ...

It has been almost three decades that the Lithium-ion Battery (LiB) was first commercialized in 1991 by Sony (I have worked at the same R&D lab! 😊).  LiBs has shown good reliability over time and now it is the most sought after energy storage chemistry for automotive and numerous other consumer applications. In this blog post, I will describe a fundamental working mechanism of a LiB. A large number of resources are available on the internet for getting insight into the LiB mechanism. I will try to give a consolidated and brief overview of: LiB charge-discharge mechanism Non-idealities in LiB operation Overview of Energy Storage Devices Figure 1 shows different types of energy storage mechanisms ranging from mechanical, electrical and chemical energy storage (it is not an all-inclusive picture. Numerous other techniques exist for storing different forms of energies)  Out of those main three types, Chemical energy storage devices are calle...