The move comes ahead of an anticipated decision to mine in early 2019, with ongoing fieldwork programmes progressing well.
Lee is currently managing director of Jialin International Trading and was previously divisional manager of AVIC International Steel Trade's mineral resources division.
Her offtake discussions will be co-ordinated alongside test work from the recently completed diamond drilling and metallurgical programmes.
Armadale said metallurgical test work at Mahenge indicated exceptional purity could be achieved alongside "excellent" flake size distribution, making the Mahenge's product "amenable to a range of commercial applications".
It said results from a simple conventional flowsheet produced grades above the standard 95% purity for most size fractions, while downstream test work on concentrates showed expandability particularly of the larger size fractions.
In addition, test work to enhance the purity of the graphite concentrate showed that acid treatment readily upgraded the concentrate to above the 99.95% purity required for the lithium-ion battery market.
Armadale said it was aiming to publish its feasibility study in the December quarter, with the 18-hole reverse circulation drilling programme completed.
The company is also almost finished its work on environmental and social baseline surveys and it expects to submit the environmental impact assessment, relocation action plan and valuation survey in October.