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When it comes to manufacturing electric vehicles, Tesla is in a unique position in the industry. As the most vertically integrated company in the auto-making world, Tesla has the ability to attack any piece or component of its vehicles or the manufacturing process to make it better and more cost effective. This is what Tesla has done with the new, revolutionary tabless batteries it is going to be using in its future electric vehicles. Why did Tesla have to make the tabless battery? Tesla announced a new tabless battery on its Battery Day event last year to critical acclaim. It was not just an academic exercise for Tesla as it was borne out of a specific need. Like other battery makers, Tesla had been purchasing its battery cells from suppliers that use their own proprietary chemistry and structure. This was working well until Tesla looked into the future and discovered that its battery supply chain could cause a problem. Tesla’s target is to sustain a 50% year on year growth in total vehicle output. For instance, last year, Tesla shipped nearly 500,000 electric cars and set a target of 750,000 for 2021. All these cars will only be shipped if they have a battery in each of them. The problem was that according to its forecast, the growth rate in the current production of batteries would not be able to match Tesla’s growth ambitions, creating a bottleneck down the road. Simply put, a time would come when Tesla would finish making its vehicles but need to wait for batteries to be finished up before installing them. The culprit here is the manufacturing process of the batteries and we shall see more on that latter. That is a scenario Tesla wants to avoid at all costs. As a result, Tesla set to work on the core components of batteries as it we know them and came out with the tabless 4680 battery. What is the difference between a tab battery and Tesla’s tabless battery? While the battery is a complex concept best left to the experts, it is possible to have a general idea of what Tesla has done here. The common cylindrical lithium-ion battery uses cells made of several layers or strips of chemical compounds to store energy. The layers are the cathode and anodes with a separator layer in between them. The cathode layer and anode layer then connect to the positive and negative terminals of the battery using small metallic components known as ‘tabs’. The problem with tabs is that they could be the downfall of the whole battery, despite performing a crucial function. They can affect the battery performance and reliability, if not done right. For instance, when the tabs are welded unto the electrodes, there could be resulting welding burrs that can pierce the layer between the cathode and anode layers, causing an internal short circuit. This has the potential of causing a fire. Also, the step of inserting the separating layer between the cathode and anode layers introduces a time consuming procedure during the battery manufacturing process. What Tesla managed to do is to eliminate the need for the connecting ‘tabs’, hence the name ‘tabless’ battery. Instead, the battery uses a conductive portion that runs along the electrode. Using this method, there less distance for the electron to travel before reaching the positive and negative terminals. This is a win for physics, as explained by Elon Musk, the CEO. So what is the big deal about Tesla’s tabless battery? The biggest deal is that Tesla has used a radically different approach in battery design. It is basically what Tesla is known for anyway, taking problems apart to be able to come up with the most fundamental solutions. With this first-principles approach, Tesla managed to change both the battery and the battery manufacturing process, making each of them better, ie both of them ended up being optimized. Well, it involved acquiring a few battery focused companies but hey, Tesla pulled it off at the end of the day. In effect, in one fell swoop, Tesla improved the efficiency and capacity of its battery, reduced the costs of production and the time taken for production. And if you think this is nothing more than a concept and will take time before actual batteries can be made, you can’t be more wrong. Tesla’s Drew Bagliano reported that they were already ramping up the production of the tabless cells in their pilot plant. Here is how the tabless design makes batteries better: With the tabless structure, as noted earlier, a time consuming step has been eliminated in the production of the battery. That is the step of inserting the tab itself inside the battery. This simply means more battery in less time. Remember Tesla foresees a shortage of battery supply as its own vehicle production increases and battery component suppliers can’t keep up the pace? Here is Tesla forestalling such a scenario. It also means batteries with larger capacities.