--- title: Batteries — a lesson of Mova's school · trees and pragmatics description: «Batteries», a lesson of the technology course of Mova's primary school, sentence by sentence with dependency trees and pragmatics. It begins: A battery is a little box of stored chemical energy. --- [Mova](https://md.mova.elamur.ai/free/en/) · [this page in HTML](https://mova.elamur.ai/free/en/corpora/school/technology/34-batteries/) [home](https://md.mova.elamur.ai/free/en/) / [corpora](https://md.mova.elamur.ai/free/en/corpora/) / [school](https://md.mova.elamur.ai/free/en/corpora/school/) / [Technology](https://md.mova.elamur.ai/free/en/corpora/school/technology/) / Batteries # Batteries Lesson 34 of the technology course of Mova's primary school: 19 sentences, each with its syntax tree and pragmatics. The lessons are written for Mova, and their agreed trees are part of Mova corpus 0.4 (CC BY-SA 4.0). How Mova does on its tests: [the lesson at school](https://md.mova.elamur.ai/free/en/school-run/technology/34-batteries/). - [0](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/0/) — A battery is a little box of stored chemical energy. - [1](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/1/) — Inside, two different chemicals are kept apart; when you join the two ends through a torch or a toy, they react and push electrons all the way round the wire, and the torch lights up. - [2](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/2/) — When the chemicals are used up, the push stops and the battery is flat. - [3](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/3/) — A rechargeable battery, like the one in your phone, can be pushed back: the charger moves the tiny particles back to where they started, ready to go again. - [4](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/4/) — Batteries come in every size, from a button in a watch to a car battery that starts the engine, a fridge-sized battery in a house, and grid batteries in rows of shipping containers that help the whole country. - [5](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/5/) — Batteries store a lot of energy in a small space, so they have strong rules: never open, burn or crush one, never mix old and new, keep chargers off beds, and take old ones to the battery bin, never the normal bin. - [6](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/6/) — In a battery such as an AA, two chemicals inside react and push electrons through the wire from one end to the other; when the chemicals are used up, the battery is flat. - [7](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/7/) — Alessandro Volta made the first battery in 1800 from a pile of metal discs and cloth soaked in salty water. - [8](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/8/) — Never open, burn or crush a battery, and never mix old and new batteries in the same toy. - [9](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/9/) — In a rechargeable phone battery, lithium moves from one side to the other as you use it, and charging pushes it back; all such batteries slowly hold less charge as they get older. - [10](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/10/) — Use the right charger, and stop charging if a phone or battery gets hot. - [11](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/11/) — A power bank is a battery in a case that stores electricity to charge phones later; never charge one overnight on a bed, and on planes it goes in hand luggage, not in a checked bag, because if it caught fire down in the hold nobody could reach it to put it out. - [12](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/12/) — A car battery is heavy, starts the engine and powers the lights when the engine is off; it contains acid, so only adults deal with it, and car batteries are among the most recycled products. - [13](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/13/) — Home battery storage keeps electricity from solar panels or cheap night power to use later, and some houses can run for a day on it. - [14](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/14/) — Old batteries go in a special recycling bin so their metals can be used again and their chemicals stay out of landfill; batteries thrown in normal bins have started fires in bin lorries. - [15](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/15/) — Two different metals pushed into a lemon or potato make a tiny current, and several lemons together can light a small LED; this is a science-class activity with low-voltage kits and an adult, never anything to do with mains sockets. - [16](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/16/) — A wireless charger has a coil in the pad that makes a changing magnetic field, and a coil in the phone turns it back into electricity; electric toothbrushes have charged this way for years. - [17](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/17/) — A battery's percentage is an estimate made by a small chip that measures the voltage and how much flows in and out, which is why it sometimes jumps. - [18](https://md.mova.elamur.ai/free/en/corpora/school/technology/34-batteries/18/) — Giant grid batteries, made of thousands of cells in containers, store electricity to smooth out wind and solar and can respond in less than a second. - ← previous: [Wind, sun and other clean energy](https://md.mova.elamur.ai/free/en/corpora/school/technology/33-wind-sun-and-other-clean-energy/) - next →: [Phones and how a call travels](https://md.mova.elamur.ai/free/en/corpora/school/technology/35-phones-and-how-a-call-travels/) - ↑ back to [Technology](https://md.mova.elamur.ai/free/en/corpora/school/technology/)