Lipo (Lipo Polymer Batteries) are used in many electronic devices. Lipo Batteries are similar to Lipo Ion batteries. They each have a nominal voltage of 3.6 volts. Unlike Lipo Ion batteries, Lipo Batteries do not have a hard metal casing but rather a flexible material encloses the chemicals inside.
The main reason for the use of Lipo cells in RC (Remote Control) plans and helicopters is that they are significantly lighter than comparable NiCad or NiMH batteries, which makes our RC airplanes and RC Helicopter fly longer and better.If you have previously been flying RC models with NiCad or NiMH batteries, switching over to lipo battery pack will result in a different number of cells being used. If you had six to seven round cells then 2 Lipo polymer cells will correctly duplicate the voltage of those cells.
There is still less of a chance of fire/explosion caused by over charging with a Nimh vs. LiPo battery. Durability is still on the side of NiMH battery packs as they can be run down to near zero volts whereas that would ruin a LiPo battery. A fourth, almost contrarian view, is that NimH batteries weigh more and put out lower voltage….an actual plus for controlled club racing and beginners. A “loose” off road track may be better traveled with a Nimh battery offering more traction and less power to break the tires’ grip. A good Nimh battery can still offer the same number of charge-discharge cycles as a Lipo battery-and without special balance chargers that Lipos require. For someone who may have reentered the hobby but still has equipment-they may choose to still use NiMH batteries.
All in all, it really depends on ones budget and application. Many hobbyists have both NimH and LiPO battery packs. Some will bash with either battery -do speed runs with lipos-or whatever they choose. With Lipo battery packs becoming cheaper, especially as new hobbyists and lipo friendly equipment enters the market, we can guess that Nimh will become less of a choice for the consumer.