North American companies are raising both cash and controversy recently in deals with Chinese firms: both American battery maker A123 and Canadian oil and gas firm Nexen have made headlines in recent weeks as some U.S. politicians question the transactions on the basis of national security. China has been ramping up foreign investment in energy as part of its efforts to meet skyrocketing demand and gain knowledge to develop its own resources. Those resources include shale gas, which has seen a boom in the U.S. and Canada thanks to the rise of hydraulic fracturing, or fracking.

Thilo Hanemann of the Rhodium Group, which tracks Chinese direct investment in various sectors of the U.S. economy, sees increased interest from