Summer Internship Report

 An aluminum-air battery uses an aluminum plate as the anode, and ambient air as the cathode, with the aluminum slowly being sacrificed as its molecules combine with oxygen to give off energy.

The basic chemical equation is:

4Al + 3O₂ + 6H₂O → 4Al(OH)₃ + energy

That is, four aluminum atoms, three oxygen molecules, and six water molecules combine to produce four molecules of hydrated aluminum oxide plus energy. Water serves as a base for the electrolyte through which ions pass to give off the energy that powers the vehicle's electric motor.

Historically, aluminum-air batteries have been confined to military applications because of the need to remove the aluminum oxide and replace the aluminum anode plates.

Israeli startup Phinergy thinks its aluminum-air energy storage device is a battery that could store enough energy to offer up to 1,000 miles of real-world range. Phinergy says its patented cathode material allows oxygen from ambient air to enter the cell freely, while blocking contamination from carbon dioxide in the air--historically a cause of failure in aluminum-air cells. Each aluminum plate, has enough energy capacity to power the car for roughly 20 miles, and the demonstrated test car had 50 of those plates. The entire battery, weighs 55 pounds (25 kilograms) giving it an energy density more than 100 times that of today's conventional lithium-ion pack.

It is also developing zinc-air batteries, which can be recharged electrically and do not sacrifice their metal electrode as the aluminum-air cells do.

Tesla CEO Elon Musk demonstrated the new battery swap process at Tesla's design studio in Hawthorne, Calif. USA. The swap process took around 90 seconds compared to almost 4 minutes it took in filling the tank of a conventional sedan. The battery-swap option allows drivers on long trips to pay for a quick change rather than wait for a recharge.

"The cost of pack swap will be equivalent to the cost of gasoline," Musk said. "That is what we are going to make sure happens at the end of the day, except that obviously it will be more convenient. It will take 90 seconds and not four or five minutes."

Tesla plans to offer the battery swap option at a number of locations around the United States, including the supercharger stations the automaker is adding over the next few years.

The battery swap will first be offered later this year supercharger stations in California. It will cost Tesla $500,000 to put the new technology into each recharging location. "We will start off with the really fast, high-traffic corridors, because the assumption here is that if you want a pack swap, time is of the essence," said Musk. "So we will start off on the I-5 corridor in California and the Boston-DC route on the East Coast and they will be co-located with the Superchargers."

Tesla has not finalized how much it will cost to put in a new battery, they expects to charge customers somewhere in the range of $60 to $80. The price will vary around the country and will be comparable to the price of about 15 gallons of gasoline where the battery swap takes place.

After a battery swap, Model S owners will have the option of either keeping the loaner battery or getting their original battery pack back. It's a small price that should not stop Tesla owners from using the service on long drives. It gives electric car owners a speedy option to eliminate range anxiety. Instead of building in a 30- or 40-minute break to recharge every 260 miles on a road trip, Tesla owners can theoretically get a battery swap in 90 seconds and it would make long drives in an electric car much more reasonable.

In the long run, Musk notes, everyone should build their own EVs and the market for credits will dry out. Tesla is working with utilities in California to help stabilize the electric grid at the charge stations. These racks of batteries from people’s cars will be part of that, so it’s at least possible that the investment in “SuperSwapping” will net out smaller than it appears given contracts with utility companies.

Israel was also the location of the company's first large-scale commercial pilot for battery-switching services. The company opened its first functional charging station the first week of December 2008 at Cinema City in Pi-Glilot near Tel Aviv.The first customer deliveries of Renault Fluence Z.E. electric cars enabled with battery switching technology began in Israel in the second quarter of 2012,and by mid September 2012, there were 21 operational battery-swap stations open to the public in Israel.

Better Place implemented a business model wherein customers entered into subscriptions to purchase driving distance similar to the mobile telephone industry from which customers contract for minutes of airtime. The initial cost of an electric vehicle might also have been subsidized by the ongoing per-distance revenue contract just as mobile handset purchases are subsidized by per-minute mobile service contracts. Better Place's goal was to enable electric cars to sell for $5,000 less than the price of the average gasoline car sold in the United States, or the impact of electric cars would be minimal.

The Better Place approach was to enable manufacturing and sales of different electric cars separately from their standardized batteries in the same way that petrol cars are sold separately from their fuel. Petrol is not purchased upfront, but is bought a few times a month when the fuel tank needs filling. Similarly, the Better Place monthly payment would cover electric "fuel" costs including battery, daily charging and battery swaps. Better Place was to allow customers to pay incrementally for battery costs including electric power, battery life, degradation, warranty problems, maintenance, capital cost, quality, technology advancement and anything else related to the battery. The per-distance fees would cover battery pack leasing, charging and swap infrastructure, purchasing sustainable electricity, profits, and the cost of investor capital.

The Better Place electric car charging infrastructure network was based on a smart grid software platform using Intel Atom processors and Microsoft .NET software, or comparable vendors. This platform was first of its kind in the world and was to enable Better Place to manage the charging of hundreds of thousands of electric cars simultaneously by automatically time-shifting recharging away from peak demand hours of the day, preventing overload of the electrical grid of the host country. Better Place would be able to provide electricity for millions of electric cars without adding a single electricity generator or transmission line by using smart software that oversaw and managed the recharging of electric cars connected with Better Place.

After implementing the first modern commercial deployment of the battery swapping model in Israel and Denmark, Better Place filed for bankruptcy in Israel in May 2013. The company's financial difficulties were caused by the high investment required to develop the charging and swapping infrastructure, about US$850 million in private capital, and a market penetration significantly lower than originally predicted by the company.

For the PHEV and EV markets to expand, developing charging infrastructure is a priority. This effort allows for charging at multiple locations, including at home and at public stations, and helps reduce consumer range anxiety.

The design, manufacture, and operation of EV and PHEV charging systems and their infrastructure have given rise to several key standards that end-users should be aware of. Safety is the most important factor that is driving the adoption of these standards. Among the agencies involved in developing these standards are: the National Fire Protection Agency (NFPA), the Society of Automotive Engineers (SAE), and Underwriters Laboratories (UL). 

Electric Vehicle Supply Equipment (EVSE) is designed to safely deliver electrical power to charge an electric vehicle.  While there are emerging and legacy charging technologies, most current EVSE utilizes conductive charging.

Conductive charging equipment is classified by the maximum amount of power in kilowatts provided to the battery. There are several levels of charging equipment. In North America, the standards are:

• 
  AC Level 1, which is a 120-volt (V) alternating current (AC) plug. A full charge at Level 1 can take between 8 and 20 hours, depending on the battery capacity of the vehicle. Charging rate is approximately 1 kW.
  

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  AC Level 2, which is a 240-volt AC plug and requires installation of home charging equipment. Level 2 charging can take between 3 and 8 hours, again depending on the battery capacity of the vehicle. Charging rates fall within a range of 3 kW to 20 kW.
  

• 
  Direct Current (DC) fast charging, which is as high as 600 V, enables charging along heavy traffic corridors and at public stations. A DC fast charge can take less than 30 minutes to charge a battery to most of its capacity.
  

It is expected that most PHEV and EV owners will recharge their vehicles overnight at home. Level 1 and Level 2 charging equipment will be the primary option for home charging. Vehicle manufacturers have already developed stations for home charging. For example, according to Nissan, in order to “pre-wire” a home charging dock for the Leaf EV, a 220/240 V 40-amp dedicated circuit is required.

In order to shift electrical load to off- peak hours Hawaiian Electric encourages EV owners to program their vehicles to start charging after 9 pm.  By avoiding charging during peak load times they avoid the need to add new “peaking” generation.  Also, in conjunction with the Time of Use rates, the Hawaiian Electric Company is to install devices to temporarily pause charging in response to grid emergencies.  Both of these programs are important to increasing our capability to utilize greater amounts of renewable energy

Public charging stations will make PHEVs and EVs more convenient, help allay range anxiety, and increase these vehicles’ useful range. Public charging stations use Level 2 or DC fast charging, and are located in high-density locations, such as shopping centers, parking lots, and garages

Asian and European countries are evolving charging standards that seek to harmonize with but may not be identical to these standards. Discussions towards broader international standards are ongoing. The Society of Automotive Engineers (SAE) J1772 Standard in North America is at the forefront of efforts to standardize charging. All major vehicle and charging system manufacturers support this standard, which should eliminate drivers’ concerns about whether their vehicle is compatible with the infrastructure. The Underwriters Laboratories verified the safety and durability of the SAE J1772 connector in 2009. The SAE J1772 Standard, which was adapted on January 14, 2010, is for electrical connections for electric vehicles, and details the physical and electric characteristics of both the charge system and coupler.

This Standard defines a five-pin configuration for the connector used for Level 1 and Level 2 charging. The connector is designed to survive more than 10,000 connection and disconnection cycles. Level 3 configurations are currently under development, as is a Direct Current fast charging configuration.