Globally, the battery recycling market is projected to grow from $12.8 billion in 2025 to $19.8 billion by the end of 2030 according to BCC Research LLC. The expanding electric vehicle market will contribute to this expansion as EVs are damaged or their batteries are degraded beyond their usefulness. This is in addition to the personal technology batteries that permeate almost every aspect of our lives.
For Redwood Materials, this has resulted in a flow of batteries in various degrees of degradation and damage that need to be taken in, assessed, and either recycled or repurposed for other uses. Determining the status of these batteries and, in particular, how safe they are to handle is vital.
Either via degradation, damage, or just being part of a vehicle that was totaled, Redwood Materials is on a mission to keep batteries in the ecosystem by recycling and repurposing EV batteries. Its recycling efforts are helping to recover over 90 percent of the materials for use in new batteries.
One of the more important ways that the company sources batteries is via a portal for junkyards. “Auto dismantlers can go onto that portal. They can put in the make (and) the model, and we’ll give them a price for that battery pack,” Andrew Hoover, Redwood Materials’ principal, risk management & product compliance, told SAE Media.
For batteries that may be damaged, special packaging is used to prevent thermal runaway during transportation. “That’s one of the things that our packaging team does with a lot of auto OEMs. They design specific packaging, returnable packaging,” Hoover said.
Redwood Materials has to comply with Damaged, Defective, or Recalled (DDR) for lithium battery shipping requirements, which are in place to mitigate the potential for fire. Occasionally, the company will need to secure a special permit for custom packaging in order to ship different types of form factors.
Once these batteries make it to the company’s facility, many are monitored and stored outside. Redwood Materials uses an air pollution control system that includes acid gas scrubbers. The batteries are monitored via a thermal imaging system that can detect the potential beginning of a thermal runaway before it gets out of control.
As for the EV batteries that come in with life in them, Redwood Materials repurposes those for Energy Storage Systems (ESS). Weirdly, the robust nature of an EV battery (high charge and discharge rates, ability to work in extreme temperatures) does not certify it as suitable for energy storage. But a path is coming.
“One of the things that I’m very proud of is Redwood sharing a task group with UL 9540 which is the ESS safety standard that will, largely, what we’re hoping for is that we’re able to develop an annex in that standard that would allow for a different path to certification for EV batteries and for other types of batteries as well,” Hoover shared.
Hoover was also happy to report that a new fire test standard for ESS was recently deployed and that Redwood Materials passed with its repurposed ESS. Although ESS are not the only areas in the battery world that require updated or new standards.
Personal mobility devices like e-bikes and electric scooters are becoming a major safety issue. Some early e-bikes used low-quality batteries that resulted in fires. These devices have also been the subject of vandalism, including being tossed in rivers and lakes. All of which results in damaged batteries.
As the market matures, quality products are out there, but there are still low-quality, low-cost mobility devices being sold to consumers.
“When you look at the number of incidents relative to the devices that are out there, you know, laptops, cell phones, AirPods, electric vehicles, energy storage systems, the incidents are relatively low compared to power mobility devices,” Hoover said. The issue is regulatory.
“There are standards for ensuring that the batteries are safe in their original use case, that doesn’t really exist yet for power mobility devices,” Hoover told SAE Media.
Fortunately, most personal devices are regulated. That doesn’t make recycling them in a safe manner easy. To reduce the hurdles of disposing of battery-powered items, there are pilot programs.
Dropping off traditional batteries at big box stores has been the norm for years. Yet for personal electronics, things get dicier. The batteries have an increased energy density compared to that of a typical 9-volt battery. “There’s really not a good framework to facilitate the consumer collection of batteries,” Hoover said.
This requires additional safety precautions. Then, there are privacy concerns that come with devices that may still have personal data stored on them. Redwood Materials tackles both these problems with a combination of old and new technologies.
The Redwood Battery Bin acts like a post office drop-off box. Once a device goes in, no one can reach in and take it out. That reduces the privacy issue. There’s still the problem of safety. If a store just has regular box or bag for these devices, it’s not thinking about the potential for fire or leaking materials.
“It’s a fire safety risk. Cardboard boxes are obviously combustible.” Hoover also points out that there may not be a smoke detection system at the front of a store if, say, a smartphone goes into thermal runaway.
Inside the Redwood Battery Bin is a metal drum. As electronic devices are dropped in, the bin deploys a proprietary blend of packing material that’s a flame retardant and absorbs any leaking electrolyte. As the barrel is filled, ultrasonic sensors check the level of devices and more packing material is deployed as needed. As a visual example, Hoover points to a yogurt parfait. It’s a strata of devices, packing material, devices, packing materials from top to bottom.
When the bin is full, the bin locks to keep more items from being placed inside. The store is alerted, and employees can replace the barrel inside and lock the filled barrel for pickup.
The smart bin also contains a fire suppression system in case one of the devices inside goes into thermal runaway.
As we use more battery-powered devices in our lives, the safe disposal, recycling, and repurposing of them is paramount to creating a world that doesn’t fall into the old habits of using once and tossing in a landfill.
Whether it’s a phone, mouse, e-bike, or EV, the batteries powering those devices at some point need to be collected, shipped, and recycled in a safe manner. Redwood Materials is working on creating an ecosystem while working with the industry to set clear guidelines on how all of this happens.
This article was written by SAE Media Group Sustainability Editor, Roberto Baldwin.
