If you've followed the development of the lithium-ion-battery industry, you may have noticed that two kinds of companies emerging: companies that promise results and those that deliver.

For years, American battery makers Ener1 (Nasdaq: HEV) and A123 Systems (Nasdaq: AONE) have talked about the promise of their technologies and the number of partnerships they've developed with the automotive industry. Yet they have very little to show for all their boasting. But while we've been distracted by federal grants and presidential speeches, Advanced Battery Technologies (Nasdaq: ABAT) has built a profitable business overseas in China.

Part of Advanced Battery's success lies in its diversified product line of battery-powered products. Ener1 and A123 are still trying to build a business by selling to auto manufacturers, while Advanced Battery Technologies is running a business by selling electric scooters, bicycles, and sport-utility vehicles and providing batteries for electric motorcycles in the United States. Its business model is similar to that of Buffett pick BYD, which sells much more than just batteries.

The following table illustrates the contrast of potential versus reality. If the electric-vehicle market takes off, Ener1 and A123 could enjoy a big-time upside, but Advanced Battery Technologies already has proven revenue and profits.

Company

Market Cap, Millions

Revenue, Millions (Trailing 12 Months)

Gross Margin (Trailing 12 Months)

P/E

Advanced Battery Technologies

$230

$81.5

46.3%

6.49

Ener1

$477

$46.1

10.2%

N/A

A123

$960

$95.2

(7.3%)

N/A

Sources: fool.com, Yahoo! Finance.

No one really knows how the electric-vehicle industry will develop or how much of its promise will come true. But whatever happens, with these three companies you have a choice between the hope of earnings and proven earnings. I'll take Advanced Battery Technologies' proven track record seven days a week over the competition.

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Fool contributor Travis Hoium owns no shares of any company mentioned here. Try any of our Foolish newsletter services free for 30 days. True to its name, The Motley Fool is made up of a motley assortment of writers and analysts, each with a unique perspective; sometimes we agree, sometimes we disagree, but we all believe in the power of learning from each other through our Foolish community. The Motley Fool has a disclosure policy.