Paleolithic body paint and perhaps in ritual. Undisputed evidence of art only becomes common in the Upper Paleolithic. Lower Paleolithic Acheulean tool users, according to Robert G. Bednarik, began to engage in symbolic behavior such as art around 850,000 BP. They decorated themselves with beads and collected exotic stones for aesthetic, rather than utilitarian qualities. According to him, traces of the pigment ochre from late Lower Paleolithic Acheulean archaeological sites suggests that Acheulean societies, like later Upper Paleolithic societies, collected and used ochre to create rock art. Nevertheless, it is also possible that the ochre traces found at Lower Paleolithic sites
Research in lithium-ion batteries they reach a non-flammable liquid electrolyte, which ferries them to the opposite electrode. The electrolyte has additives that prevent the lithium metal from reacting with it and that prevent dendrites. SolidEnergy’s technology does not require new manufacturing equipment and can be recharged 300 times while retaining 80 percent of its storage capacity. It works at room temperature, whereas some other lithium-metal batteries operate at much higher temperatures. In 2014 Seeo demonstrated a prototype of a solid-state battery, replacing the traditional liquid electrolyte with two polymer layers. One is soft and conducts ions; the other is hard and prevents dendrite formation.