Energy companies typically have low profit margins, so it isn't surprising that Sinopec is no exception. However, it is less common to find an energy company with high financial strength. Marathon Petroleum Corp. (NYSE:MPC), for example, has a cash-debt ratio of 0.05 and a financial strength score of 4 out of 10, while Halliburton Co. (NYSE:HAL) has a cash-debt ratio of 0.2 and a financial strength score of 5 out of 10.