Saturday, September 26, 2015

Are Diesel Engines More Efficient Than Gasoline Engines?

With the recent Volkswagen emissions measurement scandal, are diesel engines really more efficient than gasoline engines? 

By: Ringo Bones 

Ever since German engineer Rudolf Diesel patented his diesel engine, the industrial world was quick to embrace it with open arms given that your typical diesel engine burn about 25-percent less fuel in comparison to a gasoline engine of similar horsepower rating, not to mention that diesel fuel, as a byproduct of crude oil refinement, is around 4 to 5 times cheaper than gasoline when a barrel of crude oil produces 19 gallons of gasoline and 12 gallons of diesel fuel when it is refined. And given this “ energy utilization efficiency”, diesel engines by their very nature only produce a quarter of the carbon dioxide produced in a typical gasoline engine – which is now of paramount importance in our increasingly climate change conscious world. But sadly, diesel engines are inherently way dirtier than gasoline engines when it comes to oxides of nitrogen and particulate emissions. 

The row over whether diesel engines – as in diesel fueled cars and trucks – are really more environmentally friendly than their gasoline engine counterparts recently came to light in the form of the recent Volkswagen emissions measurement scandal where the famed German automaker was caught by the U.S. Environmental Protection Agency back in September 21, 2015 when Emissions Analytics, an internal combustion engine / automotive emissions testing lab recently uncovered that the latest models of diesel fueled Volkswagen cars sold in the United States employ a “cheating software” on its electronic engine management system that automatically reduces the engine’s power output and thus the resulting emissions output when it detect that the car is mounted on a tachometer – a device used to statically test the power output and combustion byproducts of cars under test. The Volkswagen “cheating software” allowed their late-model diesel cars to produce up to 40 times less oxides of nitrogen and particulates in a lab testing setting when compared to being actually driven on the road. 

Whether the “cheating” is deliberate or not, from a scientific viewpoint, diesel engines still produce less carbon dioxide – a potent greenhouse gas and the primary cause of the ongoing climate change – than their gasoline counterparts, but the oxides of nitrogen and particulates produced by diesel engines also have a deleterious effect on our environment and of human health. The oxides of nitrogen produced by diesel engines can promote the formation of smog and increases the acidity of rain and can also do nasty things to our lungs due to its corrosive nature. Particulates that are the byproduct of diesel combustion can increase anyone with a compromised immune system to catch pneumonia. Diesel engines may be more fuel efficient and produce less carbon dioxide than gasoline engines, but clean they are not.  

Wednesday, April 29, 2015

Stanford University’s Advanced Aluminum Battery: The Future of Rechargeable Batteries?

With several competing “futuristic” ultrafast-charging rechargeable batteries, is Stanford University’s Advanced Aluminum Battery poised to be the future of rechargeable batteries?

By: Ringo Bones

Technology experts recently quipped that if the advances made in rechargeable battery technology during the past 60 years mirrored that of semiconductors, we would have today rechargeable batteries that could power a mobile phone for a million years on a single charge. Sadly, such technology is still beyond the reach of the current major consumer electronic manufacturers, but recently, prototypes of ultrafast-charging rechargeable batteries that with a minutes worth of charging could either power a mobile phone for a day or drive an electric car for 300 miles are now a prototypical reality.

Lithium ion batteries have been a boon for the modern world in that they’ve replaced the heavier single-use alkaline type batteries in everything from wristwatches to the power supplies of flight control systems in late-model jumbo jets. Unfortunately, these rechargeable cells are already struggling to keep up with our ever increasing energy needs. But a new type of aluminum-ion battery recently developed by graduate students and their professor at Stanford University is not only less prone to bursting into flames than current lithium-ion types but can also be built at a fraction of the price and recharges completely in just over a minute. Best of all, “our new battery won’t catch fire, even if you drill through it” says Stanford University chemistry professor Hongjie Dai.

According to its developers, the Stanford University’s Advanced Aluminum Battery uses a graphite cathode, an aluminum anode and an ionic liquid electrolyte inside a polymer-coated pouch. “The electrolyte is basically a salt that is liquid at room temperature, so it’s very safe” said Stanford University graduate student Ming Gong, co-author of the study recently published in the science journal Nature.

Unlike earlier rechargeable aluminum-ion battery prototypes which generally fails after only about 100 recharge cycles, Stanford’s prototype Advanced Aluminum Battery are composed of aluminum-ion cells that can cycle more than 7,500 times without any capacity loss – that’s 7.5 times longer than your average lithium-ion rechargeable battery in current production. Sadly, Stanford University’s aluminum-ion cell isn’t perfect, yet, as it can produce only about 2 volts per cell – far less than the 3.6 volts per cell that current lithium-ion cells can muster. Plus aluminum-ion cells, at the moment, can only carry 40-watts of electricity per kilogram compared to lithium-ion’s 100 to 206 watts per kilogram power density.

“Improving the cathode material could eventually increase the voltage output and energy density” says Dai. “Otherwise, our battery has everything else you’d dream that a battery should have: inexpensive electrodes, good safety, high-speed charging, flexibility and long cycle life. I see this as a new battery in its early days, It’s quite interesting.”

Unlike other competing prototypes, Stanford University’s Advanced Aluminum Battery that has the ability to be charged for 1 minute and yet could store enough charge to power a mobile phone for 24 hours was entirely made possible by a group of graduate students and their professor without a single cent of corporate backing whatsoever. Despite of this feat, Tesla electric car company founder Elon Musk is currently skeptical of the Stanford University’s Advanced Aluminum Battery on whether it will ever be as good – or become even better than – as those ultrafast-charging lithium ion types in current development. Hmm, if only Tesla Motors CEO Elon Musk would put his money where his mouth is…

Tuesday, March 31, 2015

StoreDot’s Fast Charging FlashBatteries: The Future Of Rechargeable Batteries?

With the ability to recharge in 60 seconds to power a mobile phone or allow an electric vehicle to travel 300 miles with a 5 minute charge is StorDot’s FlashBattery represent the future of rechargeable battery technology?

By: Ringo Bones

During the 2015 Consumer Electronics Show – CES – in Las Vegas, Nevada, an Israeli firm called StoreDot demonstrated a newfangled battery technology that can power a mobile phone with just a 60-second charge and a bigger version that could drive an electric vehicle for 300 miles (480 kilometers) on a 5 minute charge. With such capability, StoreDot’s FlashBattery technology could represent the future of rechargeable battery technology where battery recharging of electric cars and other electric vehicles could be as fast as the time it takes to fill up with gasoline in your local gasoline filling station. According to StoreDot, their newfangled FlashBattery represents an evolutionary step forward of the current ubiquitous lithium ion batteries. 

Lithium ion batteries have been traditionally used for powering most portable devices and electric vehicles. While exhibiting relatively slow charging and discharging capabilities, over time, these chemical processes reduce the lithium battery’s ability to retain energy. Yet StoreDot has succeeded in isolating and maximizing the charge transfer rate and has enhanced it to heighten the superior characteristics of the FlashBattery.  

Lithium ion batteries contain inorganic compounds in the battery’s cathode, typically comprising metal oxides or polyanions which are continuously recharged by the insertion of lithium ions. This process limits ionic conductivity, thereby reducing the power density and shortening the battery’s life expectancy. Moreover, the electrolyte used in lithium ion batteries is highly volatile and flammable, posing a severe risk to consumers, critical especially in electric cars.

StoreDot’s groundbreaking solution for their FlashBattery design is a hybrid architecture using a unique hybrid multifunction electrode (MFE), StoreDot’s FlashBattery combine two types of energy storage solutions, incorporating the high-power rapid-charging capability of current super capacitor technology with the high energy storage ability and low self-discharge rate of current lithium ion batteries.

This optimized charging ability is achieved through an innovative electrode structure containing proprietary organic polymers with legacy lithium metal oxide components on the cathode end that trigger reduction-oxidation chemical reactions. This solution causes ions to flow from a modified anode to a modified cathode at a speed that could not be attained through existing lithium ion battery technologies. Together with a proprietary separator and electrolyte, this new architecture delivers a high current and low internal resistance with enhanced energy density and a prolonged battery life. 

While some battery manufacturers were able to improve only one of the following properties – either an increase in capacity, fast charging or extended battery life – StoreDot’s novel technology has optimized all three simultaneously, in addition to enhancing its safety. StoreDot’s organic compounds and newfangled proprietary battery architecture provide 4 times more charge / discharge cycles compared to any existing rechargeable battery, increasing the number of cycles from 500 to 2,000. Using compounds that are less likely to metalize during these cycles, StoreDot’s FlashBattery eliminates the risk of an internal electrical short almost entirely, which significantly prolongs battery life expectancy.

Specially designed for high current charging, StoreDot’s FlashBattery contains, in addition to lithium, non-flammable organic compounds encased in multi-layer safety-protection structure that prevents over voltage and heating and is therefore considerably safer than traditional lithium ion batteries. Containing their proprietary electrolyte which is an ecologically-friendly material, the FlashBattery meshes polymers and metal oxide together, resulting in an increased electrode stability and SEI performance at high temperatures.

Comprising carefully engineered organic molecules with high chemical stability, FlashBattery compounds can be tuned to match a variety of applications. The FlashBattery demonstrates rapid reduction-oxidation activity optimized compounds that increase the absorption of lithium ions and their counter-ions. In contrast to other batteries that contain toxic polluting heavy metals like cadmium, lead or mercury, StoreDot’s materials leave a minimal environmental footprint. And from a manufacturing engineer’s standpoint, StoreDot’s organic and polymer electrode’s raw materials are readily available thus reducing the overall cost of the battery.   

Sunday, March 29, 2015

Anode-Less Rechargeable Batteries: The Future of Rechargeable Batteries?

Even though it is an integral part of a rechargeable batteries construction for proper operation, could eliminating the anode improve current rechargeable batteries performance by leaps and bounds?

By: Ringo Bones 

Though not quite anode-less yet but a rechargeable battery manufacturing company called Solid Energy Systems is currently developing a nearly anode-less lithium ion rechargeable battery and has recently exhibited a working prototype during the 2015 Mobile World Congress in Barcelona, Spain. Given the already widespread acceptance of the lithium ion rechargeable battery in mobile phone and hybrid / electric vehicle applications, Solid Energy System’s concept takes the strengths of the current technology much further by reducing the space taken up by the anode since it takes up most of the space in current lithium ion rechargeable battery configuration. 

Solid Energy System’s nearly anode-less rechargeable battery concept could last twice as long as current lithium ion rechargeable batteries, while offering a 1,200 watt-hour per liter energy density. Designed with an ultra-thin metal anode, this configuration improves the cell-level energy density by 50-percent over current designs using graphite anodes and 30-percent improvement over silicon-composite anodes. Once marketed and used on current mobile devices, it could make them operate twice as long between recharging times. 

According to Solid Energy Systems, the “secret” in boosting energy storage lies in swapping the conventional electrode material – graphite – for a thin sheet of lithium metal foil, which can store more lithium ions. Other battery manufacturers have been trying to use lithium-metal electrodes in rechargeable lithium ion batteries for decades with only a limited success. Solid Energy seems to have solved a couple of key problems which have caused such batteries to either stop working after a few charges or burst into flames. Current carbon anode cell energy density is at 600 watt-hour per liter while silicon anode cells offer energy densities of around 800 watt-hour per liter, while Solid Energy Systems’ near anode-less cell offer energy densities of around 1,200 watt-hour per liter. 

Solid Energy Systems’ solution to make nearly anode-less rechargeable batteries to be as reliable as current lithium ion rechargeable cells without dying only a few recharge cycles or suddenly bursting to flames is via the use of both solid electrolyte and a liquid one. The solid electrolyte is applied to the lithium-metal foil, the ions don’t have to travel through this thin material, so it doesn’t matter that they are moving relatively slowly.
Solid Energy Systems’ prototype nearly anode-less battery can be recharged 300 times while retaining 80 percent of its original storage capacity – closer to what you would need in portable electronics. It also works at room temperatures whereas competing lithium-metal battery prototypes operate at temperatures too hot to be practical. As of late, most other companies investing in Solid Energy Systems’ newfangled batteries to become an economically viable commercial product are electric car / hybrid car companies with plans to use the newfangled rechargeable battery design in their electric cars.