Many new-car purchasers put off purchasing an electric vehicle because they assume the battery will fail long before the car's life is up. Engineers at Stanford University may have found a solution to this problem because their technology can extend the life of a battery by at least 20%, even when it is often charged quickly to get its energy back.
While many owners and prospective owners are understandably concerned about the battery life of electric vehicles, experience has shown that this is not the case. While it still takes longer to retrieve data from more drives, the batteries have proven to be highly reliable thus far.
While there are occasional outliers, such as the first-generation Nissan Leaf (which experienced issues due to a lack of active temperature management), modern electric vehicles can function on the original battery for many years. Many different kinds have been using the same battery for years with no problems.
But, even with today's cutting-edge technology, there is still an opportunity for improvement. That is why Stanford University engineers have dedicated their time and resources to developing technologies extending lithium-ion batteries' life. His approach to charging and discharging batteries could pave the way for a new way of producing batteries, resulting in a longer life cycle without needing additional material or technical improvements.
Electric vehicle batteries are made up of many distinct cells, each with its own unique "personality," which means that some degrade faster than others when charging and discharging. This variability is caused by variances in the manufacturing process or the materials themselves, as well as the location of the cell within the battery pack, which means it is susceptible to varying heat conditions.
One of the study's findings is that the average single-cell outlasts the typical battery pack. When a weak cell dies, though, the entire battery pack suffers. So, to avoid this situation, it is vital to consider each cell's unique properties independently and regulate the charge and discharge based on its condition. This reduces the stress on the cells, resulting in a longer life for the entire battery pack.
Because testing their theory in real life would take too long, the Stanford University scientists used a computer-generated virtual model. The findings revealed that the strongest battery cells could take the most stress, whereas those that began to disintegrate required more care. All needed to limit this degradation is to define the load conditions per cell. As a result, even when fast charging is utilized often, battery packs could last at least 20% longer between charge and discharge cycles. The same technique can draw current from each cell depending on its state and capacity during the discharge cycle.
The only issue with this new approach is that it substantially complicates the battery pack's internal electronics and makes software management more difficult because it considers each cell individually rather than as a larger set. This circumstance may increase weight, decrease battery capacity, reduce active material space, and increase the final production cost.
