$$$$ Chargers
TailHeavy,
Unless the –12 volt supply has enough capacity you will. Try not to get a power source any larger than necessary. Any voltage you don’t need has to be disposed of as heat.
The same Lithium charger can be used for LiIon and LiPoly (but NOT LiMetal). Lithium Ion has liquid electrolyte that tends to boil and produce explosive quantities of gas if mishandled while the Lithium Poly has a polymer electrolyte which, when mishandled will expand but not explosively.
Have you been able to access the URL SHenion provided?
Jay