In 2015, Benedict Evans wrote a very influential piece called “The smartphone is the new sun”. By the middle of the 2010s, it was pretty clear that that decade would be defined in many ways by the mobile computing platform that Steve Jobs unveiled in 2007. For regular people, smartphones became the locus of their lives — an ever-present tether constantly connecting them to the digital world and allowing them to navigate the physical one. For industry, smartphones and the applications they enabled became a massive opportunity for investment and profit.
Now, however, it seems like we might be reaching the end of that rainbow. The basic reason is that with smartphones, IT companies have now harvested essentially all of people’s surplus attention and time. A new Pew survey of teens’ social media habits found that almost half of young people are online “almost constantly”, up from a quarter in the mid-2010s. And smartphone penetration in rich countries is around 80%. So it’s natural for both consumers and investors/entrepreneurs to be looking around for what technologies might enable another Cambrian explosion of innovation in the next decade.
Many people think that this technology is going to be machine learning/AI. But although I do think ML will indeed be very important, I’m going to make an argument that the general-purpose technology that will really transform our society is the battery.
This is interesting because it’s a bit of a swerve from the pattern of the last four decades. From 1980-2020, the innovations that reshaped our world were all in information technology — the PC, the internet, the smartphone and the social network. But batteries are an “atoms” technology — something that powers our physical world instead of helping us spin a new digital one. So the Decade of the Battery will look more like earlier decades, in which physical appliances like washing machines, refrigerators, and air conditioning were the hot new thing.
In fact, we can already see the shift in the 2010s — after all, batteries are what enabled smartphones.
The fundamental reason that batteries are becoming so important is simply that the technology has improved by leaps and bounds. Although batteries are improving on practically any metric, the two clearest indicators are cost and energy density. The cost of batteries, measured in dollars per kWh stored, has fallen by a factor of 42 since 1991 and by a factor of 2.5 since 2010:
Meanwhile, energy density more than tripled between 1990 and 2010:
The lion’s share of this improvement was due to R&D efforts, but industrial scaling effects are starting to have a significant impact as well.
But of course that still leaves the basic question of what batteries will be used for. I’m going to go through a bunch of use cases, from the obvious (cars and energy storage) to the not-so-obvious. But first, I should talk a bit about why batteries are such a general-purpose technology.
Batteries solve two fundamental problems at once
Energy is obviously fundamental to every piece of industrial society, and it’s especially important for physical (“atoms”) technologies like transportation, manufacturing, electricity, and appliances. We often think in terms of primary energy — that is to say, where we get the energy from. Technologies like solar and wind and nuclear and hydropower supply this need, and of course burning fossil fuels does this too. Batteries don’t do this.
But there’s more to energy than generation. We also have to store the energy, and we have to transport it from place to place. In other words, we have to move energy around through both time and space, so that we can use it wherever and whenever we want. Batteries address both problems.
When it comes to storage, batteries are not yet as good as fossil fuels, because they leak energy over time. This is why they can be used for short-term energy storage for power plants and grids, but not for seasonal storage. But for transporting energy, there are some ways in which batteries are qualitatively superior to fossil fuels. First of all, a battery can be charged by basically any electrical power source, whereas an oil pipeline or a natural gas tank can only really hold one specific type of fossil fuel. Second, extracting energy from a battery is generally much less noisy than extracting energy using a combustion engine. There are other advantages too.
Most importantly, though, a battery doesn’t require a bulky combustion engine in order to extract the energy. I first realized the importance of this when I read about Portland protesters in the summer of 2020 using battery-powered leaf blowers to blow tear gas back in the face of federal agents. Battery-powered leaf blowers are less powerful than gasoline-powered ones, but they’re also much lighter. This is why we use batteries for small, lightweight drones. It’s a big part of the reason why your smartphone has a battery in it instead of a little gasoline-powered engine.
Any time some battery skeptic tells you that batteries have “lower energy density” than fossil fuels, point this out to them.
And as batteries continue to improve, their disadvantages compared to fossil fuels will decrease. We will develop batteries with longer life spans, greater power density, and so on.
The obvious use cases — cars and power storage
So, on to a big list of things we’ll use batteries for. The two most obvious cases are electric cars and electric power storage for power plants and buildings. Everyone knows by now about the EV revolution — there are Teslas driving all over our city streets. And everyone knows about solar and wind energy, and how these are intermittent and need storage in order to keep powering our buildings at night and during storms. David Roberts has a great post about this, and he notes that transportation is really the bulk of the market here:
The EV market is going absolutely vertical, while global sales of internal combustion vehicles have flattened out and are forecast to decline relentlessly. We appear to be in the midst of a rapid shift to electric cars.
And though storage for utilities is a much smaller market, that’s increasing rapidly as well:
Utility scale or building scale energy storage won’t really change our daily lives — in fact, the general idea is to prevent our daily lives from having to change as we replace fossil fuels with renewables. Electric cars, though, will definitely make the world feel different.
First of all, since electric cars charge at night, it means you’ll only very rarely have to fill up your car, instead of having to go to the gas station every time your tank is empty. As electric cars get better range — and they’re very close to gasoline cars now — this will mean that people will almost never have to stop to fill up, because their car will always start out fully charged in the morning. A big time-waster — looking for a gas station, sitting around huffing toxic fumes while your tank fills up — will mostly just vanish. It will also be a lot easier for autonomous vehicles to self-charge than to pump their own gasoline, once we get those.
Second, electric cars are much much quieter than gasoline cars — so quiet that we have to actually add noise just to prevent kids from getting run over in the street! And electric trucks will make living near highways and big thoroughfares much less onerous.
Finally, electric cars just make driving a better experience. They’re much more responsive than gasoline cars, and they’re also considerably cheaper to fill up. People who want to switch to transit-centric development won’t like this, but people who don’t have the option of riding the train will be happy.
So the well-known use cases for batteries are getting really big already. But in addition, there are a lot of less obvious but still transformative battery-dependent technologies that are growing fast as well.
Don’t sleep on e-bikes
Everyone talks about electric cars. A few people talk about electric scooters. Very few people talk about e-bikes. But more electric bicycles are now sold than electric cars in the U.S.:
E-bikes are already a $40 billion business globally, and growing fast.
E-bikes aren’t like normal bikes — they add electric power to your muscle power to produce a much easier ride. That transforms cycling in two ways. First, it allows you to go much farther. From a recent study in Norway:
The people who bought e-bikes increased their bicycle use from 2.1 kilometers (1.3 miles) to 9.2 kilometers (5.7 miles) on average per day; a 340% increase. The e-bike's share of all their transportation increased dramatically too; from 17% to 49%, where they e-biked instead of walking, taking public transit, and driving….[I]n fact, people rode their e-bikes more the longer they had them[.]
Second, e-bikes make it pretty easy to bike uphill. That opens up huge areas to cyclists that were basically denied to them before (e.g. most of San Francisco).
The combination of much longer range and not having to worry about road grades mean that e-bikes have the potential to transform the way we live. Since the U.S. already has roads and can add bike lanes where they don’t already exist, the cost of converting cities to accommodate masses of e-bike commuters will not be large (certainly smaller than, say, building trains!). And since e-bikes are small and easy to park, we can build a lot of bike racks close to common destinations, taking away some of the hassle of finding a parking space when commuting.
All in all, e-bikes will simply make it much easier to get around our cities, which hopefully will increase human connection and make us feel more free. They will also make food and product delivery a lot easier in many areas. And because e-bikes do still use a little muscle power, we might become a bit healthier too!
It’s also worth noting that electric cargo ships and planes are in the pipeline, though I don’t expect these to become common in the next decade.
Drones are the future of warfare
Batteries aren’t just going to change civilian transportation — they’re going to change military vehicles as well, enabling whole new ways of warfare. Anyone who is paying attention to the war in Ukraine already knows this. Although combustion-powered drones like the Bayraktar get most of the attention, little electric drones have started delivering precision strikes at relatively close range on the battlefield. Here is a video:
And this isn’t just because Ukraine has less money and is forced to resort to cheap crappy weapons; the Russians are using battery-powered drones as well. And of course these drones are also extremely useful for battlefield reconnaissance, which is crucial for targeting modern precision weapons.
The advent of cheap reliable energy-dense batteries makes this possible. Battery-powered drones are small, cheap, and relatively quiet. And in the era of increased geopolitical competition and conflict, innovation in military drones is probably just getting started. Anti-personnel drones to clear soldiers out of dense urban areas with minimal damage to the surrounding structures are probably on the way. Autonomous swarming drones are being developed too. And battery-powered robots may help carry equipment across the battlefield, or even carry and fire weapons previously reserved for infantry.
In the extreme scenario, humans could be driven from the battlefield completely. Batteries, with their small size, light weight, and cheap price, will probably be crucial to that.
Battery-powered everything
EVs, ebikes, and drones only scratch the surface of the transformation of our physical world that light, small, cheap energy portability provides.
First, consider appliances. Cordless equipment will gradually take over from stuff that needs to be plugged in all the time. Battery-powered air purifiers and fans and humidifiers will stand around our houses and buildings. Battery-powered kettles and crock pots and pressure cookers and other cooking appliances will let us cook food in the park. Cordless vacuums, leaf-blowers, and mowers will make it much easier to keep our houses and lawns neat and tidy. Battery-powered webcams will allow us to more easily capture much of the world on video. And so on. Just look at everything that has a cord in your house, and ask if you might want to run it far from an outlet. Batteries let you do that.
Some special kinds of batteries also have other capabilities that allow them to be used in everyday applications that most people wouldn’t think of. A really cool example is fast-discharging batteries that can be used to make super-powerful appliances.
Next, think about robots. Currently we have battery-powered roombas vacuuming our houses. Little delivery robots are starting to trundle down the street. Robot waiters are starting to appear in restaurants. And robots are going to be used in all kinds of industrial applications, from transporting parts and tools around factory floors to cleaning off solar panels. Battery-powered farm vehicles are beginning to transform agriculture.
In fact, although I said I didn’t think machine learning was going to be the #1 most transformative tech of the 2020s, it’s obviously the case that AI and batteries go together like peanut butter and jelly. As battery-powered drones and robots proliferate and fill our physical world, AI will be crucial for making sure it all runs correctly. So just as the smartphone revolution was powered by batteries, the battery revolution will be powered by AI.
Basically, the battery revolution means that the pieces of our world are starting to free themselves, get up, and move around.
Venture capitalists and technology companies, of course, stand to profit handsomely off of all this. “Deep tech” is a hot buzzword in the VC industry right now, but the big challenge is that many forms of deep tech — biopharma and other research-intensive industries — is that the long lead time and high up-front cost presents big challenges for the traditional low-cost, fast-scaling VC financing model. Battery-driven tech, however, may prove an exception. The fact that the basic research is being done in universities frees up VCs to fund applications instead of labs. And the fact that energy portability allows gadgets to adapt themselves to existing infrastructure means that investors won’t have to tussle so much with regulators or fund expensive modifications to the built environment.
There are, of course, some big obstacles for us to overcome in the Decade of the Battery. Chief among these is mineral availability. Putting batteries in everything requires mining a whole bunch of lithium, copper, cobalt, and other minerals (David Roberts, as usual, has an excellent rundown). This will require us to do a lot of mining, to shift toward types of batteries that aren’t as dependent on rare minerals, and to diversify our sources away from unfriendly regimes. It’s a challenge, but probably a doable one. And of course recycling and disposal of batteries will be a major task as well.
But no technological revolution has been without its challenges and its issues. The upside of batteries — a technology for cheap light energy portability and storage — just swamps the difficulties and downsides. It took a long time for this general-purpose technology to arrive, but now it’s here, and the next decade (or, really three decades) will see it transform the world around us.
Great writeup. I think ebikes are not as widely covered in US media because most of the USA doesn't have good bike infrastructure. Try biking to work in Houston from the suburbs or Phoenix and you'll see what I mean. Maybe as part of general densification and the revival of urbanism we can see proper bike infrastructure.
Worth noting the US just plowed a ton of money into their battery supply chains as part of the IRA. Literally every segment, plus R&D, factories, and spurred massive demand. Tens of billions. Countries are taking this v seriously as part of industrial policy.
In addition, the recyclability of metals is insane. Like 99%+, this is such a change in circularity compared to use once fossil fuels. BFD, great article!