Lithium News

When the US Naval Research Laboratory (NRL) selected Alta Devices, a Hanergy Company, as the solar solution for the prototype Hybrid Tiger UAV (Unmanned Aerial Vehicle) Project, I decided to see what I could find out from NRL. After some discussion, an NRL spokesperson said:

“Due to sponsor considerations our lab in not inclined to discuss Hybrid Tiger. However, NRL’s Solar-Soaring UAV uses photovoltaic technology and we are very open to discussing its capabilities.”

Sponsored by the Office of the Deputy Assistant Secretary of Defense for Operational Energy and the US Marine Corps Expeditionary Energy Office, the Hybrid Tiger Group 2 UAV project integrates Alta’s high efficiency solar cells, a hydrogen fuel cell, and autonomous cooperative soaring algorithms to achieve over 3.5 days of flight endurance, even during the winter solstice at up to 50° north latitude. According to Jane’s last year, Hybrid Tiger will be powered by the hydrogen fuel cell at night and solar cells during the day while carrying a small surveillance and reconnaissance payload, and first flight was expected last month, May 2018.

In the prior Solar-Soaring UAV programme, NRL tested a range of custom built solar wing sets to extend the endurance of a battery-powered, electric motor on a modified SBXC sailplane kit as detailed in the IEEE PVSC-44 paper, “Enhanced Endurance of a Unmanned Aerial Vehicles Using High-Efficiency Si and III-V Solar Cells” by David A Scheiman, Raymond Hoheisel, et al. NRL built custom SBXC solar wing sets using the following:

• SunPower monocrystalline silicon Interdigitated Back Contact (IBC) cells
• Microlink Devices’ Inverted Metamorphic Multijunction (IMM) cells
• Alta Devices’ thin-film Gallium Arsenide (GaAs) single junction cells
• SolAero Technologies’ thinned ZTJ lattice-matched triple junction cells

Another wing set using Sharp IMM cells was still in process at the time of the paper.

Without solar, the PV-SBXC UAV can fly about four hours using the 400 Watt-hour, 1.91 kg battery pack arranged as six series by six parallel (6s6p) Panasonic NCR18650B batteries. Each of the wing sets was ground tested and test flown for at least one hour. Extended endurance test flights for SunPower and Alta Devices have only been reported by NRL thus far. All the tests were flown with a fixed rectangular pattern and altitude range, and the autonomous soaring software algorithm was disabled for the two endurance flights to determine solar performance though passive soaring was permitted. The endurance flights began near sunrise with the batteries charged to at least 90% state of charge (SOC).

With the SunPower wing, the PV-SBXC UAV flew for 10.9 hours and about half of the power used during the flight was generated by the solar wing not including passive soaring. The SunPower flight benefited from two one-hour periods of thermal soaring and 40% of the flight was spent with the motor off. Correlated to a second SunPower wing on the ground, the UAV wing generated about 10% less power perhaps related to MPPT (Maximum Power Point Tracking) adjustments during aircraft motion and orientation to the sun.

The PV-SBXC UAV with the Alta Devices wing flew for 11.2 hours, and the solar wing generated almost two-thirds of the power used during the flight without any benefit from soaring. Correlated to a second Alta Devices wing on the ground, this time the UAV wing generated about 15% less power perhaps again related to MPPT adjustments during aircraft motion and orientation to the sun but also the higher Alta Devices array voltage. Alta Devices further outperformed by using only 66% of the battery capacity versus 89% by SunPower.

NRL concluded the two endurance flights demonstrated how solar power can extend UAV flight duration by over two times and even longer when paired with autonomous soaring algorithms. NRL Aerospace engineer Dr. Dan Edwards said:

“The experiments confirm significant endurance gains are possible by leveraging thermal updrafts and incident solar radiation, rather than ignoring these free sources of energy. Future testing will focus on quantifying the trade space between improvements in solar cell efficiency and combining with autonomous soaring for improved solar-recharging.”

Solar Performance Index

Alta Devices has proposed a new metric, the Solar Performance Index (P_UAV), seeking to rank solar technologies by capturing the dual concerns of power per unit area and power per unit mass in UAV designs. P_UAV is defined as the square root of the product of the power to mass ratio, P_m, and the power to area ratio, P_A.

Where:

P_m is the power to mass ratio (Watts/kilogram)

P_A: is the power to area ratio (Watts/square metre)

The units of P_UAV work out to be Watts per the product of metres and the square root of mass and do not have a physical meaning other than translating a plot of the power to mass ratio versus the power to area ratio into a single index value.

I calculated the Solar Performance Index for cells from SunPower, Alta Devices, and SolAero in tabular and bar chart form as shown below with a few caveats.

SunPower performs well considering their price to performance ratio; therefore high-efficiency crystalline silicon cells would be the preferred solution for very cost sensitive UAV applications.

Alta Devices and SolAero GaAs cells would be preferred in UAVs when endurance and weight are paramount and price is secondary.

Gen4

Alta Devices launched their fourth-generation, single junction, solar cell technology (“Gen4”) last month with the key benefits of 30% weight reduction to 170 g/m² (grams per square metre) ratio at the matrix level, including cell-to-cell interconnects, ribbons and protective diodes, and reduced thickness perfect for UAV and other autonomous power applications.

Alta Devices high-efficiency, thin-film GaAs solar cells are 100% made in the USA at their Sunnyvale, California, facility. Over the next eighteen months to two years, Alta expects to reach around 3MW of production capacity maxing out the available space and permitted capacity of the building. Alta is considering other locations for future expansion based on market demand or collocation with potential large partnerships.

Meanwhile, Alta said “more tools are landing every day” as the capacity ramp is underway through expansion and debottlenecking. Alta’s mass production process uses three unique tools for metal organic chemical vapour deposition (MOCVD), Epitaxial Lift Off (ELO), and matrix assembly. Alta Devices has created significant new Intellectual Property (IP) concerning the processes, tooling, packing factor, and weight reduction.

Alta has been using their own design MOCVD reactor and is in the process of commissioning over the next few months their latest custom designed MOCVD reactor described as much bigger than anything available. Alta’s MOCVD reactor is optimized for gas material utilization and the area based deposition required by solar cells. As a result, Alta has simplified the reactor design compared to commercial MOCVD reactors used for laser and LED production.

Alta developed another large tool to handle ELO or separation of the Gen4 GaAs thin-films from the wafer with high yield and high throughput. Alta did not disclose the current average number of lifts per wafer; wafer reuse is critical for ongoing cost reduction and capital equipment improvements.

And the Matrix Assembly tool, fed from a cell magazine, builds customized solar modules to match customer requirements via serial and parallel cell configurations. In the typical UAV application, the cell matrix built by Alta for customers includes top encapsulation for direct integration into wing materials such as carbon fibre or metal.

When I asked Alta Devices about thin-film solar cell pricing, I wasn’t sure I would get a response. However, Alta said the solar cells are UAV market value priced lower than substrate based multijunction solar cells offered by Boeing Spectrolab and SolAero, for example. At this time, Alta’s capacity is sold out to projects driven by the growth of their aerospace business.

Alta Devices future ambitions extend to the automotive market where much more competitive pricing will be required to enable range extension though still at a premium to high-efficiency crystalline silicon solar solutions.

Dual junction

As a two time, dual junction (non-concentrator) solar cell world record holder, Alta Devices updated the dual junction datasheet around the Gen4 launch and is shipping small quantities of dual junction solar cells to key customers. Dual junction cell production is planned for yearend 2018 with single junction cell production continuing in parallel.

Priced at a premium to single junction, dual junction solar cells have found two use cases in UAV applications. For the non-endurance flying market, the higher efficiency dual junction solar cells can reduce battery size and weight for the intended application enabling additional payloads. In contrast, as ongoing battery improvements increase capacity, more solar power is needed to recharge the battery favouring the improved power density of Alta’s dual junction solar cells in endurance UAVs.

Solar is poised to become a standard feature on low altitude UAVs with any reasonable surface area, typically wings, to extend endurance or increases payloads or both.

Boeing Spectrolab declined to discuss the application of their multijunction solar cells in UAV applications.

Samsung is reportedly leading the race to build foldable smartphones with the development of a curved battery that it can produce in large numbers.

The Korean conglomerate is said to have figured out a way to make large-capacity batteries that can store between 3,000mAh and 6,000mAh of power, reports ITHome. If the news is accurate, it’d be a far cry from the 210mAh flexible cell design that the Samsung SDI subsidiary came up with four years ago.

The company is slated to begin a pilot manufacturing run of flexible OLED screens; Korean outlet ET News reports that these could be incorporated into what’s being called the Galaxy X phone, which will go into production next year.

As for the display, we’ve been hearing about Samsung’s attempt to create a foldable screen since 2011, when it showed off a prototype. At the time, the company said the display could be opened and closed 100,000 times before its brightness dropped by 6 percent.

But we still don’t know what the Galaxy X might look like. According to Pocketnow, the key aspects of the flagship’s design were undecided even in mid-April; all we heard was that the screen might actually be comprised of two displays that come together when the device is opened up.

The word on the street is that Samsung’s foldable device cost about $1,900 when it launches. But it’ll be interesting to see if it can beat its rivals to the punch, as reports from last year suggested that Apple, Huawei, Xiaomi and ZTE are also working on similar devices.

Growth in “Lithium Consumption” accelerated in 2017, by over 10 per cent on 2016 levels, to reach 211,000t lithium carbonate equivalent (LCE), according to new research.

The lithium-ion battery industry continues to be the main catalyst for the growth of the lithium market; it accounted for close to 50 per cent of consumption in 2017 and is expected to reach over 80 per cent by 2027, according to a study by metals and minerals research firm Roskill.

David Merriman, deputy division manager at Roskill, told Impact4All: “The battery industry is going through a lot of change as the costs of Li-ion batteries are falling, they are more competitive than lead or nickel, they have a much better energy density and they are lightweight.”

The battery industry is going through a lot of change as the costs of Li-ion batteries are falling, they are more competitive than lead or nickel, they have a much better energy density and they are lightweight.

The manager said that burgeoning EV growth in China is driving the boom but ‘lithium growth is increasingly becoming a global story’.

Merriman said that while there is no shortage of lithium in the ground there is currently a 12 to 18-month lag time to process the lithium into useable battery products. He added: “There is a big need for investment in this area.”

Huge demand

Automotive applications were the largest market for Li-ion batteries in 2017, with Chinese sales of plug-in electric vehicles (PEV) increasing by around 20 per cent y-o-y, said the study. This placed strain on the battery supply chain which is likely to continue, with Roskill estimating that Chinese PEV sales could reach around one million units in 2021.

The lead-time between first purchase of lithium compounds and then subsequent use in Li-ion battery applications created by the automotive industry supply chain increased ‘demand’ ahead of consumption by nine per cent in 2017, a trend which is expected to intensify over the coming years. Demand for lithium is expected to approach 1.0Mt LCE in 2027, said the Roskill report.

Forecast strong demand growth has incentivised the expansion of existing assets and the development of new lithium operations. The build-out of new and expanded capacity is expected to continue the oversupply of mined products, and extend to refined products towards 2020.

Price peak expected in 2018

Lithium prices continued to increase in 2017, for both contract prices, and Chinese spot material. Lithium carbonate and hydroxide prices are forecast to peak in 2018, before greater supply availability causes prices to fall back in 2019.

“A price floor of $11,000/t battery-grade lithium carbonate is expected, before continued demand growth for battery grade lithium compounds applies greater demand-side pressure on prices beyond 2021,” the report said.

“The premium for battery-grade lithium hydroxide over lithium carbonate is expected to re-emerge in the short term, but could disappear with more independent lithium hydroxide production from mineral concentrates,” it said.

Kokam Co., Ltd, the world’s premier provider of innovative battery solutions, today announced the launch of its K-UPS series of high power Uninterruptible Power Supply (UPS) battery racks. Featuring Kokam’s Ultra High Power Lithium Nickel Manganese Cobalt Oxide (UHP NMC) battery technology, the new battery racks enable UPS system providers to meet growing data center demand for lithium-ion UPS systems that can deliver high power for a short period of time at a lower cost than UPS systems using lead-acid batteries.

Growing Data Center Market for High Power, Short Duration UPS Systems

Developers and operators of data centers are increasingly installing backup generators to produce power during long power outages. These long-term backup generators decrease the need for UPS systems that can provide a high level of power for a long period of time, as these facilities now require high power for only a short period of time (less than 15 minutes), until the backup generators can come online. However, most UPS systems use lead-acid batteries, and lead-acid batteries’ low power discharge rates force data center developers and operators to purchase high capacity, long duration UPS systems to address their facilities’ short-term, high power needs. This is leading data center developers and operators to seek new, more affordable UPS systems that require fewer batteries than lead-acid UPS systems to deliver the same amount of power. In addition, lead-acid UPS systems have large footprints, are heavy, require high maintenance, need significant cooling and ventilation and have to be replaced every 3-5 years.

Industry-Leading High Power Performance Reduces UPS Costs for Data Centers

The K-UPS battery rack uses Kokam’s industry-leading high performance lithium-ion UHP NMC batteries, which feature up to a 10 C-rate compared to a 2 C-rate for most lead-acid batteries or a 4 C-rate for most other lithium-ion batteries (C-rate measures the rate a battery charges or discharges relative to its maximum capacity). This high power output enables UPS system providers to use fewer batteries in a UHP NMC battery UPS system than lead-acid or other lithium-ion battery UPS systems, while delivering the same amount of power. For example, K-UPS battery racks can provide up to a 500 percent more power at the same level of battery capacity as most lead-acid UPS systems, or up to 250 percent more power at the same level of battery capacity as most other lithium-ion UPS systems. By using fewer batteries in their UPS systems, UPS system providers can lower the overall cost of these systems for data center developers and operators, while still providing them with the high power, short duration performance they need.

K-UPS Battery Racks Deliver Size, Weight, Lifetime, Cooling and Ventilation Benefits

UPS systems using Kokam’s K-UPS battery racks have other advantages over UPS systems using lead-acid batteries, including:

• Smaller System Footprints: Thanks to its higher power density, a three square foot UHP NMC battery can deliver the same amount of power as a 10 square foot lead-acid battery, reducing the amount of space data centers need for their UPS systems by 70 percent or more. Data centers can use this space for additional revenue generating equipment, helping them increase their revenues.
• Lower Weight: With fewer batteries needed to deliver the same amount of power, UPS systems using K-UPS battery racks can be up to 5 times lighter than lead-acid UPS systems with similar power, reducing shipping costs. In addition, the lower weight of UPS systems using K-UPS battery racks provide data center developers and operators with additional flexibility — allowing them to install their UPS system on any floor of the data center without needing to make major modifications to the data center’s structure.
• Longer Lives: UHP NMC batteries can last up to 15 years, compared to 3-5 years for lead-acid batteries, significantly reducing UPS Total Cost of Ownership (TCO).
• Reduced Cooling and Ventilation Costs: Lead-acid batteries require a temperature range between 20 – 22.5 degrees Celsius to operate reliably, while UHP NMC batteries can operate in temperatures ranging between 18 – 28 degrees Celsius, allowing data centers with UPS systems using K-UPS battery racks to reducing their cooling costs. In addition, unlike many lead-acid batteries, the UHP NMC batteries in K-UPS battery racks do not emit hydrogen, reducing datacenter costs related to ventilation.

K-UPS battery racks come in both 2 pole and 3 pole configurations at a variety of different voltage levels, providing design flexibility to UPS system providers. In addition, drawing on its 20 years of high-power battery technology experience, Kokam can offer UPS system providers customized K-UPS battery racks. Kokam has already delivered 23 MW of K-UPS battery racks to customers and is scheduled to deliver 50 MW of K-UPS battery racks this year to customers in Australia, Asia and Europe.

“Though the UPS market is still dominated by lead-acid batteries, rising data center interest in more affordable, compact, long-lasting, lightweight UPS systems is growing the market for high power UPS systems using lithium-ion batteries,” said Ike Hong, vice president of Kokam’s Power Solutions Division. “Our new K-UPS battery racks use our UHP NMC batteries to deliver UPS system providers the industry-leading power discharge rate they need to build high-power UPS systems with the price, size, footprint, weight, lifetime and other characteristics that data center developers and operators increasingly demand.”

Just because an electric-car battery isn’t performing to the best of its ability doesn’t mean it’s destined for the trash heap.

Nissan announced last week that it had finished installing a Leaf-battery-based energy storage system at Amsterdam’s Johan Cruijff ArenA (yes, that’s how they capitalize it). Capable of storing 3 megawatts of power, the equivalent of 148 new and used Leaf batteries will work with Eaton power converters to provide a more sustainable method of powering the arena.

“The ArenA is assured of a considerable amount of power, even during an outage,” said Henk van Raan, the arena’s director of innovation, in a statement. “As a result, the stadium will contribute to a stable Dutch energy grid. The Johan Cruijff ArenA is one of the most sustainable stadiums in the world and leads the way in introducing smart innovations like this unique energy storage system.”

It’s not just pulling power from the grid for later use, either. The arena has 4,200 solar panels on its roof, which can generate power for later use, as well. It won’t be used for primary power, but rather as a backup in case of outages and as a supplement during periods of heavy use. This will greatly reduce the arena’s reliance on pollution-happy diesel generators and reduce strain on the grid during concerts and other power-hungry events.

Reusing old EV batteries in this way isn’t necessarily a new idea. Last December, Roadshow looked at the growing trend of reusing EV batteries for other purposes. Nissan has an entire subsidiary dedicated to finding ways to reuse these batteries. Chevrolet has used old Volt batteries to supply backup power to one of its data centers. Other automakers, like Fiat, have teamed up with firms dedicated to keeping salvageable batteries in use, too.

There is never a dull moment in the lithium ion battery business. When not dealing with cobalt supply issues including hoarding, battery makers are faced with trying to cope with supplying not only exponentially increasing demand, but the fits and starts that come with circumstances at individual companies.

As the latest, a Panasonic executive VP who heads the company’s automotive business has told reporters that the company “would of course consider additional investment” in the Telsa/Panasonic battery gigafactory “if we are requested to do so”, as reported by Reuters.

This would come on top of the $1.6 billion that Panasonic is already putting into the Nevada gigafactory, which plans to not only be the world’s largest factory but its largest building by square footage. However, Panasonic Executive VP Yoshio Ito says that the company has not made any formal decision regarding further funding.

Such an investment may be needed, given the reports of battery cell shortages in the wake of an uptick in Tesla Model 3 production. Ito has reported “occasional battery (cell) shortages”, following the increase in output.

Tesla has confirmed the production increase, stating that it produced more than 5,000 Model 3 vehicles in the last seven days of Q2, and expects to reach 6,000 per week by late July. The Model 3 had previously suffered from production delays, which gave the company a black eye and resulted in a fall in stock price.

“The last 12 months were some of the most difficult in Tesla’s history, and we are incredibly proud of the whole Tesla team for achieving the 5,000 unit Model 3 production rate,” reads Tesla’s statement. “It was not easy, but it was definitely worth it.”

Stationary battery impact?

It is unknown what impact, if any, these supply and investment dynamics will have on Tesla’s stationary lithium-ion battery business. The company’s Q1 energy storage deployments grew 161% quarter-over-quarter to 373 megawatt-hours, but those numbers are tiny compared to what is to come.

Tesla is also bidding for some of the largest battery-storage projects ever built, including a 182 MW battery for PG&E which could be the world’s second largest battery, if the six-hour rating rumors are correct.

Regardless, globally the stationary lithium-ion battery storage business is much smaller than the business of supplying batteries to electric vehicles (EVs). The scaling of battery manufacturing for EVs is driving price declines for stationary batteries, but this could also mean that such batteries are subject to the mood swings of the larger EV market and supply chain.

Tesla has characteristically made no public comments regarding cell shortages at the battery gigafactory, and thus none about any potential impact to its stationary battery business. pv magazine was awaiting a response to our questions at press time, and we will update this article if we receive any reply.