Li-ion cells are used for energy storage and conversion in multiple applications, including electric vehicles and renewable energy. Unfortunately, Li-ion cells are very temperature sensitive. A high-rate discharge may result in significant heat generation, which, if not properly managed, may lead to overheating and thermal runaway. On the other hand, operation in low temperature ambient results in significant performance degradation. Most thermal management approaches investigated in the past do not address both cooling and heating requirements for a Li-ion cell. This paper investigates dual-purpose thermal management of a Li-ion cell using solid-state thermoelectric elements. Experiments show that a thermoelectric element can effectively cool down a cell, resulting in negligible surface temperature rise up to 5C discharge rate. By simply reversing the polarity of thermoelectric current, the same thermoelectric element is shown to cause rapid heating of the cell in a low temperature ambient. Experiments show that in a 0 degrees C ambient, the cell surface temperature rises to 20 degrees C within 10 s with 1.5A thermoelectric current. Experimental data are shown to be in good agreement with a numerical simulation model. Even though high power consumption and cost may be important concerns, the seamless switching between heating and cooling functions makes thermoelectric elements an attractive option for thermal management of Li-ion cells in specific applications.