I just read yet another news article where an RC hobbyist lost his garage, and almost his entire house, to a lipo fire. He was charging a lipo in a ceramic pot, but he forgot to put the lid on. The charger malfunctioned and the battery flared and set the wall behind on fire. Next to the pot were a dozen other lipos, and they went up next. The hobbyist used up two fire extinguishers holding the fire at bay until the fire department arrived to finish the job. He was only away from the charger for five minutes when the incident occurred.
Always store, charge, and transport your lipos in an enclosed and fire resistant container. Store them in a dry place around room temperature if you can, and don’t let the containers rest directly on the floor if that surface is flammable (wood, carpet, etc).
Princess Auto has an array of steel ammo cans from $30 to $40 each in their Surplus section that make excellent battery storage containers. The .50 cal “fat” cans are 8 x 7 x 12 inches and are a useful size. They are all rubber gasketed and have a positive locking latch.