More than one in five cars sold globally in 2024 was electric, with sales crossing 17 million — a new record. And similar trends are emerging across other vehicle types, such as electric trucks, electric bikes and U.S. electric school buses.

This marks a much-needed shift toward cleaner, healthier transportation that doesn't warm the planet or pollute the air. Yet rising EV use also presents a burgeoning challenge: How to manage the influx of retired batteries?

The amount of EV battery power needed globally is projected to triple in the coming years, from 1 terawatt-hour (TWh) in 2024 to 3 TWh in 2030. A typical EV battery is expected to last 8-12 years on average, after which it must be removed and replaced. At the current pace of EV sales globally, experts predict there will be about 20,500 kilotons of end-of-life batteries by 2040 — roughly 55 times the weight of the Empire State Building.

So, what happens to these batteries at the end of their life in a vehicle? How do we ensure they don't become a threat to people or the environment? And, critically, whose duty should it be to ensure they're managed responsibly?

We explored how some countries and U.S. states are addressing these questions — particularly through a policy known as "extended producer responsibility" — and what to watch on the road ahead.

Many electric cars lined up on a lot for sale.
EVs for sale on a lot in China. Rising EV use globally will lead to an influx of retired batteries that must be managed with care to avoid potential health and environmental risks. Photo by Wengen Ling/iStock

The Challenge with EV Batteries

Used EV batteries are classified as hazardous waste in the U.S. and elsewhere. There's currently a lack of consensus on the best approach to handling this waste, and while solutions are starting to emerge, concerns around its potential environmental and social impacts are growing.

Batteries left in landfills can leach toxic chemicals that pollute soil and groundwater. This can expose nearby communities to severe health risks, including developmental and reproductive disorders, kidney damage and skin allergies. Ecosystems are also affected; for example, soil contamination can hamper plant growth and cause toxic chemicals to accumulate throughout the food chain.

Fires, which can happen during transport and at waste management facilities, recycling centers and landfills, are another major risk of mishandling batteries. EV battery fires are especially dangerous due to "thermal runaway" — a chain reaction of rapid, uncontrollable temperature and pressure increase within a battery that causes fires to burn hotter and release toxic fumes. This also makes them particularly difficult to extinguish.

Battery fires can expose workers to hazardous gases, metals and chemicals that can cause injuries and long-term respiratory damage. The risks are especially acute for workers in the informal sector (such as in developing countries, where waste is often shipped) who may not have the right training or equipment to safely handle used batteries.

The key to preventing such risks is keeping battery waste out of landfills and ensuring it's handled safely. This requires strong regulations around collection, repurposing and recycling. Yet progress in this area has been piecemeal. In the U.S., for example, recycling programs are largely voluntary, and battery recycling rates remain below 15%.

What Happens When an EV Battery Expires?

If an EV owner notices that their car has a lower driving range, slower charging, a warning light or a system issue, this can mean its battery is ready to be retired. The next step would typically be to take the vehicle back to the dealership or to a service center to either replace the battery or sell the car.

Importantly, EV batteries at the end of their "first life" aren't fully spent. Many still retain around 70%-80% of their original charge and could be put to use in less demanding applications, such as renewable energy storage. But they need to be assessed and rerouted for this purpose rather than thrown away.

Once they're removed, batteries are inspected for their state of health and safety characteristics (like flammability, ignitability, corrosivity and toxicity) to determine whether they can be reused or recycled. This can be done by specialized technicians at the dealer, outsourced to a partner company, or managed by waste handlers. After this, the batteries are dismantled, and their various components are sent to landfills, recycling facilities or repurposing centers as appropriate.

Much battery waste, at least from the U.S., is exported to other countries (often low-income) where it is handled based on local legislation.

Infographic showing the waste management process for used electric vehicle batteries in the U.S.

The problem is that this system is far from airtight. For one, EV owners may not know who collects used EVs or EV batteries near them. If they aren't able to access a collection facility, or if their dealer lacks capacity and infrastructure, they might go to an informal auto dismantler. Once the battery is taken out of the vehicle, it is no longer covered by warranty, and its ownership is unclear. This can result in "orphan batteries" that are nobody's responsibility to collect or safely dispose of. In addition, most battery collection infrastructure in the U.S. is located far from facilities for recycling or repurposing, increasing transportation costs and the risk of fires en route.

The process of discharging old batteries and assessing their remaining health, if done improperly, can also expose workers to toxic metals, chemical spills and fires. These risks are exacerbated in countries that import e-waste or secondhand vehicles from abroad, as well as at informal vehicle dismantlers within the U.S. These places may lack regulation and enforcement, formal worker protections, and proper training and safety gear.

Who Should Be Responsible for Used EV batteries?

Keeping EV batteries out of landfills, mitigating safety risks, and increasing reuse and recycling will require oversight at each stage of their end-of-life journey. There needs to be an authority to take responsibility for ensuring that used batteries are collected, assessed and utilized to their full capacity — and paying for the process.

That's where extended producer responsibility (EPR) comes in.

EPR policies are intended to hold producers responsible for their products throughout the entire lifecycle. They are already used in some places for products like electronics, appliances and mattresses. For EV batteries, extended producer responsibility means putting the onus for end-of-life management on vehicle or battery producers, rather than consumers or waste handlers.

Most regions with significant EV adoption, including the EU, India and China, already have some form of EPR in place for EV batteries. But while a few U.S. states are following suit, the country lacks a national law.

How Do EPR Policies for Used Batteries Work?

While their broader design varies, all EPR laws have a minimum requirement for manufacturers to collect a percentage (often by weight) of the total product they place on the market. This could include working directly or indirectly with retailers to educate car owners on best practices and set up collection infrastructure; with waste haulers to help ensure safe transportation; and with recycling centers and repurposing facilities to aggregate batteries and data and determine the next best use for end-of-life batteries. Producers may even receive economic benefits by controlling end-of-life batteries, such as through revenue sharing agreements with repurposing or recycling companies.

Some EPR laws also include measures to increase rates of recycling, repurposing or remanufacturing. For example:

  • The EU batteries directive requires that battery manufacturers minimize their environmental footprint by using specified amounts of recycled minerals in new batteries or designing them to be more repairable.
  • The New Jersey Electric and Hybrid Vehicle Battery EPR law explicitly bans disposal of EV batteries in landfills and imposes a fine for doing so, incentivizing manufacturers to ensure all used batteries are collected. It also encourages repurposing, as partner companies could acquire a higher volume of used batteries from the manufacturers at a more predictable cost and quality.
  • India's Battery Waste Management Rules allow producers to leverage deposit refund schemes or buy-back policies to incentivize car owners to return used batteries. They also require producers to use up to 20% recycled minerals in battery production by 2030.

In addition, EPR laws often include a component on public education to ensure that consumers are aware of how to handle used EV batteries and have access to information on drop-off points or dealership services.

  • Voluntary Producer Responsibility Programs for Used Batteries
  • While government policies are critical, better battery management can also happen from the bottom up. For example, over 25 companies in the U.S. set up a voluntary EPR program — the eBike Battery Recycling Program — to help manage their used e-bike batteries safely and ensure they are recycled. For a nominal cost (less than 1% of total vehicle price), a third-party organization tracks batteries placed on the market by participating companies and assesses their value at end-of-life. This cost is borne by the manufacturer, and the third-party organization aggregates, transports and safely recycles the used batteries.

EPR Laws Show Promise, but Hurdles Remain

While EPR laws related to EV batteries are relatively nascent, similar regulations for other commodities have proven to significantly increase collection, recycling and reuse. For example, British Columbia enacted an EPR law for residential packaging and paper in 2014, which increased their collected waste by over 60% in a single year. Japan's Home Appliance Recycling Law obliges retailers and manufacturers to collect and recycle specified household appliances; this led to over 15 million units collected in FY2021, with recycling rates above 90% for certain appliances — exceeding expectations. Meanwhile, a 2021 report by PBL Netherlands Environmental Assessment Agency claimed that approximately 75% of all collected battery material in the country was reused in 2019. Such examples shed light on the promise of a well-designed EPR regulation for EV batteries.

However, these laws aren't without potential pitfalls. For example, manufacturers could pass the cost of battery management onto consumers by raising EV prices, which risks deterring some buyers and slowing the transition to EVs.

While the goal of an EPR law is to collect used batteries locally and build a domestic supply chain for reuse and recycling, this isn't guaranteed. E-waste is often shipped from wealthier to low-income countries, with very little retained and recycled domestically (around 20% in 2017). Exporting materials such as black mass (shredded battery scrap) simply shifts the environmental and safety burden to a different region.

Finally, with a loosely regulated battery collection market, waste haulers, retailers and producers may find it valuable to hoard used EV batteries in anticipation of rising demand and the potential for greater profits later. If batteries aren't stored safely, this could increase the risk of fires and dangerous chemical leakage.

Solar panels tilted to the sun in a green field.
Used EV batteries still hold much of their original charge and can be repurposed for other uses, like renewable energy storage, if they are collected and handled responsibly. Photo by Soonthorn Wongsaita/Shutterstock

What's Next?

The U.S. currently lacks a national battery EPR law, although its Environmental Protection Agency is developing a national EPR framework. Meanwhile, many states are moving forward on policies and regulations. New Jersey was the first state to pass a used EV battery collection law, and others (including Washington, California, Hawaii, Illinois and Massachusetts) are in various stages of designing their own.

Other countries are exploring the prospect, too: In Australia, the Auto Recyclers Association is advocating for an EPR law and the adoption of the Global Battery Passport to increase collection rates and transparency in the battery supply chain.

For policymakers, expanding EPR laws — such as passing national laws in the U.S., Australia and elsewhere — is a good first step toward more responsible battery management. Equally important will be streamlining these policies and regulations between and within countries to make it easier for companies to comply and to help regulate waste flows across borders. This is particularly crucial for countries with active trade agreements related to used vehicles. Laying guardrails in EPR laws that require used batteries to be retained in the country or region could ensure that most collected batteries are repurposed and recycled domestically, encouraging energy security and helping limit e-waste exports.

Meanwhile, building consumer awareness about the drawbacks and opportunities from used batteries could help mitigate any potential adverse impacts to EV adoption. Companies in specific segments, like electric school buses, have a chance to lead the way through voluntary EPR programs, giving customers (i.e. school districts) certainty that their used batteries are being managed sustainably. As school buses are in every community, there's an added benefit of setting up partnerships and infrastructure with nationwide coverage.

Ultimately, EPR is just one of many strategies needed to enable a truly sustainable and circular battery value chain. Complementary policies can help ensure that used batteries are managed responsibly and not landfilled overseas, typically in low-income countries. Policies like a federal ban on landfilling and limits on exporting used EV batteries could help incentivize producers to create a safe and circular system.