What a difference a year makes.

In August 2008, battery-maker A123 Systems filed papers to hold an initial public offering to raise $175 million, amid economic turmoil and concern among some investors that the company would not get the contract to supply batteries to the Chevy Volt.

This week, the company held an IPO that raised $380 million dollars and allowed the company to sell its stock for $13.50 a share, above the earlier estimates that the stock would sell for between $8 and $11.50.

And today, traders responded by driving up the price of the stock to $20.18, a 50.3 percent increase on the first day of trading.

So what happened? Although A123 lost the Volt contract, it subsequently signed a deal to supply Chrysler with batteries for its cars. Other car manufacturers have also said they will jump into the race for electric cars, boosting the potential market. Lithium-ion batteries – A123's stock in trade – will likely play a big role for temporary energy storage for utilities.

On the financial side, the company also raised another $69 million in the spring. Then came the pivotal election of Barack Obama and the stimulus plan. A123 landed a $249 million grant from the Department of Energy to build a manufacturing plant: it was one of the largest DOE grants and one of the few ones given to a startup.

The company also continued to tinker with its technology, said Doug Widney, an independent battery consultant.

"The year in delay has been healthy," Widney said.

The big questions now are whether the one-day pop will translate into continued gains and whether the results will cast a halo upon other battery companies or other green companies contemplating an IPO.

It's hard to say. A123 has lost a cumulative $146 million since beginning operations, but it has pulled in $168.5 million in revenue and landed deals with large corporations. The batteries it has cumulatively shipped can hold 107.5 million watt/hours. Many other would-be competitors have not even begun mass production yet.