Groundbreaking Battery Announcement? 400Wh/kg

I woke up this morning to read of the Envia energy company talking about how they had breached the 400Wh/kg battery barrier. While the average person has no idea what it means, lets just say thats 3-4x better than batteries available today in early 2012. These batteries wont be available until 2014 with smaller improvements between now and then (200-250 Wh/kg batteries available in late 2012-2013).

Extraordinary claims require extraordinary proof. 

Luckily, Envia seems to understand this. They’ve had the cells tested at private labs, and as well by the US Naval Surface Warfare Center. From the report’s conclusion.

The test results from the prototype cells tested at [NSWC] Crane were in line with the results obtained from the manufacturer. The claims of 400 Wh/Kg were substantiated through the cycling tests performed at Crane. This is a 160% energy density increase over the industry standard indicated in paragraph 5.1 [Panasonic's 2011 year 18650-cell battery, 3.6Ah 245Wh/kg]

The cells are built around a cathode licensed from Arggone National Labs. The cathode was first licensed in 2007. The anode is developed using the new silicon nano-technologies used in other batteries (the new late 2012 Panasonic and Sony cells are supposed to use Si anodes and a significant boost to capacity).

The second big announcement is price – they tout a $180/kWh price tag for these cells. That is approximately 1/4 the price of batteries in 2010, and 1/2 the price of batteries today, and roughly the price expected for batteries in 2015 (around when the cells are set to hit the market). The recent stories about Tesla replacement batteries costing $40,000 for 53kWh (full pack price), this would be only cost about $10,000 (batteries only). If you look at the Tesla Model S incremental battery prices ($10,000 for 20kWh more), this dramatically undercuts those prices by roughly half – instead of $10,000 more for 20kWh, it could eventually be $5,000 more.

Battery Math

These batteries are very well suited for full EVs. A 300-mile pack for a Nissan Leaf style vehicle would be the same size and weight as the current pack and cost about the same as the initial cost of the pack in 2011. The five characteristics – capacity, power, weight, volume and cycle life – are sufficient for EVs — 85kWh, 250kW, 210Kg, similar to the current pack size, and 275,000 miles on the pack to 80% original capacity. This battery would yield about 275-300 miles per charge. A cut down pack that offers 150 miles would offer 150,000 miles, along with half the weight and power (but still enough for an EV).

For plug-ins, these batteries would probably need to be in up-sized packs based on power needs (the pack needs to be able to produce enough power to push the vehicle up steep mountain grades and pass on the highway). So a Volt pack might go from 16 to 20kWh. The bouns would be more extended range (from 35 miles to 40-45), and longer life on the battery, the battery would still be smaller, lighter and cheaper (welcome back 5th seat!) at 1/2 the size, 50kg, and only around $3,500 instead of $8,000 or so.

It isn’t really suitable for hybrids or small plug-ins (Prius Plug-in), not without an adjustment to the manufacturing to change the battery characteristics from high density to high power (you’d want to sacrifice energy storage for power/kg).

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