Better Electrolytes for Better Batteries

June 2, 2012

I’ve written here a number of times about the quest to develop new battery technology, most recently about the further development of sodium ion battery technology.  There are many possible combinations of electrode materials, physical design, and electrolyte chemistry to be explored.

According to an article at Technology Review, a start-up company in Colorado, Boulder Ionics, claims to have developed a new process for manufacturing special ionic liquid electrolytes that would enable higher-performance batteries.

The electrolyte, made from ionic liquids—salts that are molten below 100 ⁰C—can operate at high voltages and temperatures, isn’t flammable, and doesn’t evaporate. Ionic liquids are normally expensive to produce, but Boulder Ionics is developing a cheaper manufacturing process.

These ionic liquids are normally produced in batches, but the company says that it has developed a continuous process that requires less time and simpler equipment to produce the electrolytes.   It also says that its process is safer (the synthesis of ionic liquids can involve highly exothermic reactions), and produces a higher purity product.  These liquids, by the way, are not exactly household names; they are fairly complex organic salts; for example:

Iolyte-P1 is an ultra-high-purity grade of 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide (CAS #174899-82-2)

In theory, the use of these ionic liquid electrolytes could allow substantial improvement in the storage capacity of existing battery types, such as the lithium ion batteries used in all our portable gadgets and in electric vehicles.  They could also ease the development of metal-air batteries (such as lithium-air batteries), because the ionic liquids will not evaporate.

As in all these early-stage developments, there are unanswered questions about how well the technology can be implemented on an industrial scale.  The majority of these ideas will probably turn out to be duds; if one or two work out, though, the payoff could be large.

A Black Box for your Car, Revisited

May 16, 2012

About a year ago, I posted an article here about the possibility that the US government, specifically the National Highway Traffic Safety Administration [NHTSA], might soon require all new automobiles sold in the US to be equipped with event data recorders [EDRs]. the so-called “black boxes”.  Similar devices have been used for years on commercial aircraft. and the data obtained from them has been of great value in understanding crashes and improving safety.  As I mentioned in that earlier post, many newer cars already have electronic data recorders of some sort.  These have proved to be useful in accident investigations, although how they work and what they record has been, until quite recently, pretty much up to the automaker.

A recent article at Wired provides an update on what’s happening in this area.  At present, although there is no mandate to equip cars with EDRs, the NHTSA’s regulations do specify that, if an EDR is installed, it must collect a specified set of data.

Since 2006, NHTSA has required that consumers be informed when an automaker has installed an EDR in a vehicle, although the disclosure is typically buried on the car’s owner’s manual. More recently, NHTSA mandated that vehicles manufactured after September 1, 2011 that include the devices must record a minimum of 13 data points in a standardized format.

Congress is now considering legislation that would require EDRs to be installed on new vehicles.

[US Senate] Bill 1813 that mandates EDRs for every car sold in the U.S. starting with the model year 2015 has already passed the Senate. The U.S. House of Representatives is expected to pass a version of the bill with slightly different language.

There are privacy concerns about the collection of this data.  At present, the proposed rules say that EDRs can only collect data related to vehicle safety; but it is not hard to imagine that some security agencies might think that recording GPS coordinates might be a useful little enhancement.  Then there is the question of who owns that collected data.  The pending legislation says that the data belongs to the owner or lessee of the vehicle, which is good.  But it’s likely that the devil is in the details, and the ownership rules will need to be carefully drawn.  For example, the article points out that, if a car is “totalled” in a crash, it typically becomes the property of the insurance company.  The company might, in some cases be tempted to declare the car a total loss in order to own the EDR data for use in legal proceedings.

There is a strong case, on safety improvement grounds, for collecting this kind of data.  WE just need to do our best to ensure that it is not misused.

Living with Driverless Cars

May 13, 2012

A couple of days ago, I posted a note on Google’s receiving approval to test its driverless cars in Nevada.  If the technology proves successful, and is adopted to any significant extent, it will probably change how we drive, and how we think about driving, possibly in unexpected ways.

The BBC News Magazine has an article on how some of those changes might play out.  Some of the changes would very likely be positive.  An automated driver will not be talking or texting on a cell phone,  sightseeing, or otherwise diverting its attention to something other than driving.  It will not be sleepy or intoxicated, and will have faster reaction times than a human driver.  That should mean fewer crashes.  Automated driving might also allow more traffic to be carried on the same roadway, because cars could travel closer together, particularly if vehicles are able to communicate with each other, as in the “road train” experiments.  The automated driver can also be programmed to avoid human drivers’ dangerous behavior.

When the car is on self-driving mode, it doesn’t speed, it doesn’t cut you off, it doesn’t tailgate.

Some of the changes suggested in the article seem to me a bit more problematic.  It suggests that the technology might make auto use available to people who currently, because of physical infirmities, cannot drive, such as the elderly, or people with epilepsy.  The article also suggests that a self-driving car could, in effect, run errands on its own.

A car could take the children to school early in the morning, then return home on its own to pick up the parents for their commute.

After a late-night carouse, a drinker could find and reserve a hire car on their phone, then have it pick them up and drive them home.

I’m sure that, properly used, the technology could make driving safer, and allow some people to drive who would otherwise be only marginally capable.  But the idea of having the vehicle operate without at least one competent adult along, in case of emergency, strikes me as ill-advised; I hope that we will require a lot of evidence of the technology’s reliability before we begin that experiment.

IBM’s Breathing Battery

April 22, 2012

I’ve written here several times before about the importance of better battery technology to the effort to use more energy from renewable sources (such as wind or solar power), and to the development of better electric vehicles.  While autos like the Toyota Prius, which have hybrid gasoline-electric power, have been reasonably successful (helped, of course, by tax and other incentives), the development of all-electric vehicles has been held back by the relatively low power to weight ratio of current batteries.  Gasoline’s big advantage as a vehicle fuel is that it has a high energy density, the amount of power that can be generated per kilogram of fuel.

Back in 2009, IBM launched a research project, called Battery 500, aimed at developing new battery technology that would allow an electric vehicle to travel 500 miles on a single charge.   The project cites consumer surveys that indicate that “range anxiety”, the fear of being stranded without power, is a significant obstacle to consumer acceptance of all-electric vehicles.

Electric cars today typically can travel only about 100 miles on current battery technology, called lithium-ion (LIB). LIB technology stands little chance of being light enough to travel 500 miles on a single charge and cheap enough to be practical for a typical family car.

Now, according to an article at Wired, IBM has demonstrated a prototype lithium-air battery that the company believes has the potential to power a car for 500 miles.   (The ExtremeTech site also has an article on this development.)  The idea of a lithium air battery is not new; one of its key attractions is that, because one of the reactants, air, is taken in from the outside rather than having to be built into the battery, weight and size are reduced.  In the approach developed by IBM, oxygen from the air is taken into tiny openings in the battery cell, about 1 angstrom (10-10 meter) across.  The oxygen then reacts with lithium ions on the battery cathode, producing lithium peroxide and electrons, and thus electric current.  Charging the battery reverses the chemical reaction, releasing oxygen back into the air.  Theoretically, this technology should be able to achieve an energy density of about 12 kWh/kg, roughly 15 times that of lithium-ion batteries.

There is considerable work still to be done to turn this development into a practical product; some of that will probably decrease the energy density somewhat.  Nonetheless, this is a significant step forward, because it has the potential of achieving an energy density at least roughly comparable to gasoline.

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