Can Argon be used to charge a lithium ion battery? If so, does the battery have to be connected via battery connector or can it be soldered to Li+ pin?
@MohamedEmara, welcome to the Community! Yes, the Argon can charge a single cell 3.7v LiPo and it can be connected either via the battery connector or the Li+ pin.
Thank You. Is that the case for lithium-ion batteries too?
Yes, a LiPo ( Lithium-Polymer) is essentially a Lithium-Ion battery packaged in a flexible polymer casing, instead of a cylindrical cell.
However, “Raw” cylindrical cells , or “Un-Protected” LiOn cells should not be used with Particle devices.