Supercapacitors explained - the future of energy storage?

this episode is brought to you by brilliant click the link in the description below with tesla's battery day event not too far off and their acquisition of maxwell technologies last year i thought it was worth taking a closer look at supercapacitors some believe that supercapacitors might be integrated into the future of evs but what exactly is a supercapacitor and what makes them so different from batteries are they really the future of energy storage i'm matt farrell welcome to undecided [Music] before we get into the nitty-gritty of whether super capacitors can really change energy storage all on their own it's worth taking a look at what they are and how they're different from something like a lithium-ion battery both batteries and capacitors are a method of storing energy but lithium-ion batteries rely on chemical reactions to store and release their energy it's made up of a positive and negative side which are called the cathode and the anode these two sides are submerged in a liquid electrolyte and are separated by a micro perforated separator which allows ions to pass through when the battery charges and discharges those ions flow back and forth between the cathode and the anode during this process the battery is heating up expanding and contracting and these kind of reactions degrade the battery over time giving batteries a limited life span but one benefit of a battery technology is a very high specific energy or energy density so it can store a lot of energy for later use but capacitors are different they don't rely on chemical play in order to function instead they store potential energy electrostatically capacitors use a dielectric or insulator between their plates to separate the collection of positive and negative charges that are building on each plate it's this separation that allows the device to store energy and release it quickly it's basically capturing static electricity one benefit of this is that a three volt capacitor now will still be a three volt capacitor in 15 to 20 years time while a battery may lose voltage capacity over time and use and unlike a battery a capacitor has much higher power throughput so it can charge and discharge in a fraction of the time but they have a very low specific energy it's good for very small bursts of power and that's where super capacitors enter the scene they start to bridge the gap between battery and capacitor the concept of a supercapacitor is not a new thing though in fact in 1957 the first supercapacitor device was created by general electric but there aren't any known commercial applications from that time in 1966 standard oil accidentally discovered the double layer capacitor while working on fuel cells but it wasn't until the late 1970s the japanese company nec began commercially offering the first super capacitor for computer memory backup in fact while we commonly refer to many products as super capacitors or ultra capacitors those two terms are used interchangeably and really depends on what company is producing it and what they want to call it for the most part it's really just a trademark thing in the 1990s products such as econ's ps cap which is a starter for diesel trains began hitting the market and pushing the boundaries of energy storage and capacitor applications companies like maxwell technologies murata and tekate generally dominate the supercapacitor field but recent developments in graphene based capacitors are once again pushing the growth of supercapacitor efficiency and application but i'll talk more about that a bit later first we need to talk about how a supercapacitor works and how it's different than a regular capacitor because it's kind of cool it's starting to venture towards a battery's design and use an electrolyte on either side of an insulator when current is applied ions build up on either side of the insulator and create a double layer of charge what makes a supercapacitor truly superior to a normal capacitor or even a battery is the distance between the metal plates in a normal capacitor the distance is around 10 to 100 microns and a micron is one thousandth of a millimeter but a supercapacitor that distance is narrowed to one thousandth of a micron and that smaller distance leads to a larger electric field or more energy not to mention the carbon-coated plates and supercapacitors increase the available surface area for storage capacity by up to a hundred thousand times that's a lot more energy available for use than a normal capacitor so what are these power hungry little titans used for we're really just at the beginning of super capacitor applications but in general they've been found to have the biggest potential for application in hybrid transportation cue the tesla maxwell speculation here toyota peugeot mazda and even lamborghini have all released models of vehicles that use some combination of supercapacitors and conventional lithium-ion batteries believe it or not even though tesla invested 200 million dollars to purchase maxwell technologies elon musk has said his focus is not on expanding the use and development of maxwell's supercapacitors for tesla vehicles but instead their battery manufacturing technology however cars like toyota's hybrid r concept car and lamborghini's high-powered xeon are using supercapacitors for a very specific role power regeneration systems during deceleration in other words when cars are slowing the energy generated from that action is stored by supercapacitors on board and later used for acceleration saving batteries for less strenuous actions it's taking advantage of a supercapacitor's superior power throughput a fantastic example of how effective supercapacitors can be is right in switzerland where fleet of buses will be exposed to charging stations at a variety of stops along their route just 15 seconds can top the energy charge off and only a few minutes would be needed to give it a full charge from nothing with frequent top offs it makes up for the lack of energy density and storage and because super capacitors can draw a lower current over a period of a few minutes at a time this puts less stress on the grid however supercapacitors still can't compete with lithium-ion batteries when it comes to that high specific energy and long-term energy storage but despite that some companies are making progress on projects that are poised to make supercapacitors more universally applicable you may have watched my recent videos on graphene and carbon nanotubes well those materials are actually playing a role in the future of supercapacitors companies like nawa technologies and skeleton technologies have taken supercapacitors to the next level by incorporating graphene into the coating on the metal plates they've taken this and expanded the conventional use of supercaps into markets like components for e-motorcycles spacecrafts and wave energy technology graphene provides the next generation of supercapacitors with an interesting array of improvements in particular graphene offers substantially more surface area giving supercapacitors even more capacity for energy storage but in addition to that graphene is ultra light and has unique elasticity and is incredibly strong in fact nama technologies skeleton and other supercapacitor battery companies have already found major applications for their graphene-based super capacitors skeletons products can be found helping power major tram systems in big european hubs like warsaw and manheim but it's not just trams and urban transportation that skeleton has found a use for they're working with the european space agency on a potential approach for sudden power usage on satellites and spacecraft as well as developing an ultra capacitor module for use in wind turbines to help manage the blade pitch control nawa is now a racer in e motorcycle that packs a serious punch is showing the world what an ultra-capacitor lithium-ion hybrid power system can do in smaller vehicles by making this bike incredibly efficient while the bike itself isn't being rolled out for commercialized sail what it's doing is proving to other companies interested in the potential of super capacitors that this technology is groundbreaking the bottleneck and absorbing all of the regenerative braking power is the battery which has a very slow charge rate the supercapacitor combo allows it to recoup about 80 to 90 percent of the energy from braking and then immediately reuse that for acceleration but wait there's more eaton's supercapacitors are built to pair with battery systems the unkazoo opto electronics fast charging laptop battery system earthdash supercap battery mixture for e-bikes and motorcycles and zapgo's e-scooters are all examples of small power management companies that are experimenting with application of supercapacitors in their technology with all of these examples there doesn't seem to be any mass movement towards the replacement of batteries with super capacitors in everyday technology so why is that well the short answer is that supercapacitors while superior to traditional capacitors and their ability to store and release energy are still not able to replace the function of conventional lithium-ion batteries mainly because lithium-ion batteries pack a punch that supercapacitors can't in the form of specific energy or energy density lithium-ion batteries have about a 250 watt hours per kilogram versus ultra capacitors at about 20 watt hours per kilogram but even companies that focus on supercapacitor technology like skeleton technologies admit that a hybridization of lithium-ion and supercapacitor-driven power systems could propel electric technologies into the next era and the reality is that most of the applications that we see today are some sort of combination between the two when a supercapacitor is placed in parallel with a traditional battery we see drastic changes in the battery lifespan the process essentially works like this the presence of a supercapacitor in parallel with a regular battery basically just reduces the workload and intensity level that the battery has to endure giving the battery more longevity in some research it's shown that it can extend the life of a battery by up to four times so why are we seeing this in all evs well battery technology and evs is currently good enough and it's getting better for how we're using it the expense for going down this path may not be worth the investment for technology that's nearly 65 years old supercapacitors have yet to really find their place in electric technology but it seems that in unison with lithium-ion batteries and with graphene being applied more and more commonly supercapacitors are slowly building themselves an important role in hybrid technology and that's something that's easy to overlook the importance of streamlining and improving efficiency of current technologies by adding not replacing a component to the mix supercapacitors could play that role making lithium-ion batteries which have high energy density more useful over longer and longer periods of time the potential is there for supercapacitors to take charge of the energy storage game and redefine what energy storage really is we still have ways to go but it will be very interesting to see how they're applied not just to electric cars buses and other transportation but to renewable energy and the grid as well and if you'd like to dive a little deeper on the underlying principles of supercapacitors like static charge and how protons and electrons move attract and repel each other check out the electricity and magnetism course at brilliant this has been one of my favorite courses so far but even if you're not attracted to learning about magnetism see what i did there they have over 60 courses including topics in computer science physics and mathematics they teach all of the concepts through fun and interactive challenges which helped you understand the why of something not just the how this is really tapped into the way i learn it helps to develop your intuition and is my favorite part of brilliant so go to brilliant.org undecided to sign up for free the first 200 people will get 20 off their annual premium membership thanks to brilliant and to all of you for supporting the channel so what's your take jump in the comments and let me know what you think about super capacitors and if you think tesla may end up using them and as always a special thank you to all of my patrons all of your support is really helping to make this possible if you like this video be sure to check out one of the ones i have linked to right here and be sure to subscribe if you think i've earned it and as always thanks so much for watching i'll see you in the next one

Channel: Undecided with Matt Ferrell

Views: 549,274

Rating: 4.9351001 out of 5

Keywords: supercapacitor, supercapacitor batteries, supercapacitor battery, supercapacitor car, supercapacitor graphene, supercapacitor vs battery, ultracapacitor vs supercapacitor, capacitor, engineering, explain, explained, graphene, lithium ion battery, maxwell technologies, maxwell technologies ultracapacitor, new technology, science, storage, super capacitor, technology, tesla, ultracapacitor, undecided with matt ferrell, renewable energy

Id: -7T-6XdiRTw

Length: 11min 27sec (687 seconds)

Published: Tue Sep 01 2020

Reddit Comments

[u/excelsior2000]

A solution to a problem that we're forcing on ourselves. We could just, you know, not have the problem.

The only reason to need all that energy storage is if we're using too much unreliable, inferior power sources.

[u/logicalprogressive]

Not quite as rosy as the video made it sound.

• Battery voltage falls at little as it discharges while a capacitor's voltage must fall to zero to fully discharge it.

• An 18650 is a very popular lithium battery cell. Costs about $5 and stores about 10 Watt-hours (36,000 Joules) of energy. This is about the same amount of energy stored in a 10,000 Farad cap rated at 2.7V. A supercap the same size as an 18650 Li cell (18mm dia X 72mm) is 100 Farads and costs $11. It stores 365 Joules or about 1% of what the Li battery can store. 100 supercaps are required costing $1,100 to equal the $5 Lithium cell.

• Supercaps have a relatively short rated lifetime, about 1,000 to 2,000 hours at 65C.