A123 soars as much as 41 percent in debut

* A123 shares start at $17, premium of 25.9 pct

* A123 shares reach as high as $19.00

Lithium-ion car battery maker A123 Systems Inc (AONE.O) shares soared as much as 41 percent in their debut on Thursday in an eagerly anticipated initial public offering.

A123 started trading at $17 on Nasdaq following the company's IPO on Wednesday, when the stock price came in higher than anticipated and more shares than expected were sold.

The company sold 28.1 million shares for $13.50 each in the IPO. The upsized deal helped it raise $380.4 million.

If A123 holds onto its gains, it would rank among the IPOs this year with the greatest first-day pops.

A123, which was founded by scientists linked to the Massachusetts Institute of Technology, develops batteries and battery systems for hybrid electric vehicles, plug-in hybrid electric vehicles, and electric vehicles and works with such carmakers as BMW (BMWG.DE), Chrysler and General Motors Co [GM.UL]. (Reporting by Phil Wahba; Editing by Lisa Von Ahn)