Scientists at the National Renewable Energy Laboratory (NREL) and Northern Illinois University (NIU) have successfully prevented lead from escaping damaged perovskite solar cells. The research effort is their latest work in addressing concerns about potential lead toxicity.
The light-absorbing layer in perovskite solar cells contains a small amount of lead. Simply encapsulating solar cells does not stop lead from leaking if the device was to become damaged by severe weather conditions, such as a hailstorm. Instead, chemical absorption holds the key.
The authors are Fei Zhang, Jinhui Tong, and Kai Zhu of NREL; and Xun Li, Jianxin Wang, and Tao Xu of NIU.
“It is valuable to develop an approach that can be applied to various perovskite solar cell configurations,” Zhu said.
Zhu and some of the same researchers in 2020 reported successful experiments in sequestering lead should a perovskite cell become damaged. They developed lead-absorbing films, applied them to the two sides of a cell, and then smashed them with a hammer and slashed them with a knife. The damaged cell was then immersed in water. The scientists found the films prevented more than 96% of the lead from leaking into the water.
Researchers elsewhere followed up on the lead concern and developed a resin that could be incorporated into a perovskite solar cell. But, as the NREL and NIU scientists noted, “These additional modifications could complicate the device fabrication and configuration and potentially limit device performance and scale-up.”
Instead, the authors noted in the paper, a better proposition is to develop durable and highly efficient lead-absorbing components that can be “conveniently mounted” onto the perovskite solar cell as an accessory.
The NREL and NIU scientists believe they have found a solution in using a tape-like chemical absorption approach that can be readily installed on both sides of a perovskite solar cell. In a series of tests, the tapes captured almost all of the lead leakage without compromising the cell’s performance and operation. The tapes were made of a standard solar ethylene vinyl acetate (EVA) film and a pre-laminated di(2-ethylhexyl) methanediphosphonic acid layer.
After damaging the perovskite solar cells, the scientists conducted a series of tests to quantify how much lead would escape into water. In one experiment, the concentration of lead in water that fell on the damaged device averaged about 19.14 parts per million. The tape brought that figure down to 2.13 parts per billion. To put this figure in context, the Environmental Protection Agency considers water safe to drink if the lead content is less than 15 parts per billion.
“Since EVA has been extensively used as a cost-effective and durable encapsulating material for silicon-based solar panels, the integration of lead-absorbing materials with EVA provides an industrially ready and stand-alone component to facilitate the future market adoption of perovskite solar cells,” Xu said.
The Department of Energy’s Solar Energy Technology Office funded the research.
Volkswagen is advertising its 2024 ID.4 Standard at $999 down, $149/month for 24 months. That’s an average monthly lease cost of just $184/month plus tax and license, making it the cheapest of all January EV lease offers we’ve found.
We haven’t seen a great lease deal like this on a five-passenger electric SUV since last April, when Toyota slashed the average lease cost of its bZ4X XLE down to $191/month for 2023 model and $227/month for a 2024 model. In-stock bZ4X inventories were depleted in a few weeks, and dealers subsequently started to hike their asking prices as they collected deposits for ordered and in-transit vehicles. It stands to reason that the same phenomena could occur with this incredible ID.4 lease offer, so act quickly if you’re intrigued by this deal.
Equipped with a 62kWh battery and a single motor that drives the rear wheels, the ID.4 in Standard trim (MSRP $41,160) can travel 206 miles on a full charge and achieve 60mph from standstill in 7.3 seconds. Consumers that require more range or performance can opt for an array of higher trim levels, ranging from the ID.4 Pro RWD (291 miles, 0-60mph in 6.1 seconds, MSRP $46,300) to the top-of-the-line fully-equipped ID.4. Pro S AWD (263 miles, 0-60mph in 4.6 seconds, MSRP $55,300).
For those that prefer to buy rather than lease, Volkswagen is running a $10,500 Retail Customer Bonus Cash incentive on the ID.4 which means that the ID.4 Standard can be bought for just $30,660.
As far as dealer offers, a quick survey of a few VW dealers shows that VW of Thousand Oaks in southern California, VW of West Islip in New York and King VW in Maryland have dealer discounts of about $2000 that should stack on top of manufacturer incentives to lower the monthly cost of a lease or reduce the final price on a purchase.
Hamburger Hochbahn AG operates the city of Hamburg’s bus system, and they’ve just placed an order with Daimler Buses for 350 fully electric Mercedes-Benz eCitaro buses to be delivered to the northern German city for use as zero-emission public transport.
Hamburger Hochbahn AG becomes the latest bus operator to put in a major order with Daimler – as I type this, fully 95 examples of the Mercedes-Benz eCitaro electric buse have already been deployed on the streets of Hamburg through Vhh.mobility, with both Mercedes and Vhh.mobility calling the bus fleet’s arrival a major step towards CO2-neutral local transport.
“I am very pleased that, together with vhh.mobility, we can make a significant contribution to emission-free local transport in the Hamburg metropolitan region,” says Till Oberwörder, CEO of Daimler Buses. “Our battery-electric eCitaro city bus offers an excellent overall package: The modern, long-range electric drive ensures that passengers reach their destinations quietly and locally CO2-neutrally. Advanced assistance systems also increase safety in all road traffic conditions.”
When discussing their order, Hamburger Hochbahn AG representatives said they were particularly impressed by the low total cost of ownership (TCO) and the ease of maintenance offered by the Mercedes eCitaro electric bus over its service life.
Electric equipment from XCMG can now be ordered with interchangeable battery swap tech, enabling heavy trucks and construction equipment to swap out their BYD-developed, 400 kWh battery packs in just three minutes, and top-off as quickly as diesel.
And we’re not just talking about off-highway and heavy equipment – the XCMG’s swappable BYD batteries are making their way to on-road trucks as well … but we’ll get to that.
XCMG ZNK95 electric autonomous haul truck
XCMG showed off its latest electric equipment at last month’s Bauma China show, including an updated version of its of its 85-ton autonomous electric mining truck. Known as the ZNK95 (above), the truck features a fully cab-less design – meaning there isn’t even a place for an operator to sit, let alone operate. That’s too bad, too, because what operator wouldn’t want to experience a dedicated permanent magnet synchronous electric drive system capable of putting out 800 kW (1070 hp) and 22,000 Nm (16,200 lb-ft) of torque?
But autonomous solutions aren’t about hp and torque – they’re about keeping operators out of extreme and dangerouns environments. To that end, XCMG says its new HDEVs are fully capable of operating in high-altitude, extremely cold environments with temperatures as low as -40°C (a temp. that most diesels wouldn’t be able to start at, let alone run).
Even in those extreme climates, the XCMG gets the job done with an autonomous driving system that integrates a number of multiple cutting-edge technologies that combine environmental perception, decision-making and planning, vehicle control, and communication into a single dashboard that can be monitored by the fleet manager.
The system can even diagnose faults on individual vehicles and bring them back to service before they break down in the field – a huge potential problem if a truck or dozer gets caught underground!
The ZNK95 has already been deployed at a large, open-pit mine in Inner-Mongolia, China, that has adopted a comprehensive unmanned and electrified construction solution from XCMG Machinery for its latest “green” mining operation. The company says the mine will emit 149,000 fewer tons of harmful carbon emissions than it would with diesel haul trucks annually by the time its full order of ZNK95s is delivered in 2026.
But wait, there’s more …
If you needed a reminder that China is light-years ahead of the US when it comes to electrification tech (and, yes, I know light-years measure distance and not time – grow up), you should know that XCMG’s swappable battery tech, which features 400 kWh packs using BYD blade-style battery cells packed at a facility that’s run as a JV between XCMG and BYD, is such a non-event in a country that’s seen millions of swaps that it didn’t even merit a press release at Bauma.
In fact, the only reason I know about it at all was because I follow Etrucks New Zealand, an XCMG dealer, on LinkedIn, and he was talking it up.
“XCMG are by far the dominant EV exhibitor at Bauma Shanghai. Here a truck crane solution to swap construction machine batteries,” said Ross Linton, owner and President of Etrucks New Zealand. “Here a truck crane solution to swap construction machine batteries.”