CEO Policy & Research Team : Maria Eisemann & Samantha Reifer
Halloween is a time of year that people play with the symbology of fear and death through revelry, costume and candy. It could also be a time of year that brings a shorter lifespan to the energy application that powers electric cars.
Being in the year 2016 most of us in Colorado (and in the United States) are well accustomed to batteries. But few of us actually understand how they work and how to best preserve their life power, leading to a range of anxieties that surface when people think about purchasing electric vehicles. Where am I going to charge? When is my battery going to die? How often should I charge? What do I do with it when it’s dead? And ultimately who am I going to turn to for answers? There are a lot of good questions in the case of battery life cycle, thus Maria and Sammy of the Colorado Energy Office went out trick or treating to find out what is so frightening about the life and death of a battery.
The first door we knocked on was Google’s search engine which led us to researchers at the National Renewable Energy Laboratory (NREL) in Golden, Colorado, a dexterous laboratory that has been working on a multitude of research projects on batteries (and other energy related projects). A knock on this door and we were fortunate enough to be treated to Ying Shi, Andy Hoke, and Kandler Smith’s time for a couple of phone calls to decipher some of the frightening tales we have heard about the battery. These are their stories. (Cue in Law and Order “dun dun dun”)
QUESTION: What is the average lifespan of a battery?
FACT: For vehicle applications productive use is about 10 years.
“The warranty is ten years for most cars, and is the number that is regularly used in research to represent battery lifespan” say Ying. “This is [the point in time] most OEMs [original equipment manufacturer] see 20% to 30% reduction in their battery usable energy and power and the range is still acceptably close enough to the original promised range of the electric vehicle”
“Batteries are actually usable in electric vehicles until 50-60% of their original battery capacity” says Kandler “But with that, you only have 50-60% of the original range” Andy adds. Time though is more significant than anything else, which is supported by the fact that Andy points out: “Tesla’s battery warranty is for 10 years and unlimited miles”.
“Batteries age like humans do...you won’t be running in your fifties like you do in your twenties and that is the same as a battery” Ying tells. Like anything that exists in this world, time conquers all. Though motor vehicles have set the bar high where some motor engines can last 15-20 years, electric batteries also save you money over the ten year warranty period since you avoid maintenance costs such as oil changes and regular engine repairs. Plus, electric batteries for vehicle applications are relatively nascent, and rapidly improving with time.
QUESTION: How do I preserve or even extend the life of my battery?
FACT: Batteries do not like it hot.
“There is a saying, that batteries die in the summer but their funeral is in the winter.” says Kandler. Though most of us notice the immediate deficiencies of technology when we are on top of a mountain skiing or in any type of colder environment, the actual harm that is caused to a battery is when it gets incredibly hot. So the first thing you can do to help preserve your battery’s life? Park in the shade, “especially in places like Colorado where there is high solar radiation” says Kandler.
There are a few other good habits that you can develop as a car owner to help increase the longevity of your battery. Firstly, cut back on driving trips that would deeply discharge your battery below 15% remaining charge. This appeals to your common sense, the less you use an object in general, the less wear it is likely to face. Batteries that are frequently and deeply cycled are subjected to near-constant charging, leaving the battery little inactive time to cool off. Secondly, don’t use fast charging to power up your vehicle if you can avoid it. This causes your battery to get really hot over a relatively small period of time, and when that happens it can cause degradation. Thirdly, cut back on your charging all together. If you can make it to the office two days in a row without a charge, do it! “Charging beyond the recommended limit is bad” comments Ying. “The most interesting outcome from our study, to me. was that lithium ion batteries don’t want to be at full charge too often and degrade more quickly when they are.” includes Andy.
QUESTION: What do I do with my dead battery?
FACT: The battery is not yet dead. (It’s just a flesh wound.)
“Batteries are actually viable enough for second generation grid and storage applications after their useful life within a vehicle is complete.” says Ying. “Even though it is only at 80% of it’s original storage energy, there is still a lot of capability left in that battery.” states Kandler.
Many car manufacturers, including GM, Nissan, and Chevrolet are using old car batteries for second generation electricity applications. Nissan is working on creating a whole product market for these used batteries with Green Charge Networks. The intent is to create and sell stationary storage systems built around used Leaf batteries for businesses. While GM also plans to sell stationary storage systems eventually, they also have been using old batteries for personal applications, such as the five Volt batteries they use to help run one of their data centers. At this data center, “the batteries are available to either store or feed energy as needed [in support of the solar panels and wind turbines they have on site], with excess power going into the grid.” Plus “the batteries can hold four hours’ worth of backup power for use in a failure” (NY Times, Cardwell)
Many EV manufacturers have been working on developing sustainable ways to dispose of, repurpose, or recycle their old vehicle batteries. If storage continues to gain popularity, used EV batteries will be a real contender for cheaper and more green alternatives to items such as Tesla’s product branch of storage technologies made from new batteries.
CASE: Battery death is not as frightening as it may seem. As a relatively nascent technology for vehicle applications, the development of the battery shows a lot of promise for opportunity and now with the millions of dollars and thousands of hours of manpower being thrown behind developing batteries, EVs and storage capabilities are just getting better and better every year.
Plus, there are a lot of actions you can take as a conscious consumer to help preserve the life of your EV battery. Fun fact, these tricks (listed above) work for other technology battery packs as well, such as your laptops’ and cell phones’.
All in all, ten years of battery life is a long time, a treat really. Though it may be scary to say goodbye after those long years together, know also that you battery is still strong and powerful and can have an “afterlife” for storage and grid applications to help renewable plants operate or a business's lights stay on during a power outage. And who knows what other applications they can be used for in 10 years! Kind of like a pillowcase full of candy on late October night.