Electric current

Battery (electricity)

In science and technology, a battery is a device that stores chemical energy and makes it available in an electrical form. Batteries consist of electrochemical devices such as one or more galvanic cells, fuel cells or flow cells. Strictly, an electrical "battery" is an interconnected array of similar cells, but the term "battery" is also commonly applied to a single cell that is used on its own.
With technological progress, various types of batteries have been developed for use in diverse ways. Their applications range from portable electronic devices to automobiles and space probes.

Four double-A (AA) electrochemical cells.

A schematic of an electric battery

Batareya (elektr)
Ilm-fan va texnologiyada batareya kimyoviy energiyani saqlaydigan va uni elektr shaklida mavjud qiladigan qurilma. Batareyalar bir yoki bir nechta galvanik hujayralar, yonilg'i xujayralari yoki oqim xujayralari kabi elektrokimyoviy qurilmalardan iborat. To'g'rirog'i, elektr "batareya" - bu o'xshash hujayralarning o'zaro bog'langan massivi, ammo "batareya" atamasi odatda o'z-o'zidan ishlatiladigan bitta hujayra uchun ham qo'llaniladi.
Texnologik taraqqiyot bilan har xil turdagi batareyalar har xil usullarda foydalanish uchun ishlab chiqilgan. Ularning qo'llanilishi portativ elektron qurilmalardan avtomobillar va kosmik zondlargacha.

Electrical conductivity

Electrical conductivity or specific conductivity is a measure of a material's ability to conduct an electric current. When an electrical potential difference is placed across a conductor, its movable charges flow, giving rise to an electric current. The conductivity σ is defined as the ratio of the current density J to the electric field strength E:
It is also possible to have materials in which the conductivity is anisotropic, in which case σ is a 3×3 matrix (or more technically a rank-2 tensor) which is generally symmetric.
Conductivity is the reciprocal (inverse) of electrical resistivity and has the SI units of siemens per meter (S•m^-1) i.e. if the electrical conductance between opposite faces of a one-meter cube of material is one Siemens then the material's electrical conductivity is one Siemens per meter. Electrical conductivity is commonly represented by the Greek letter σ, but κ or γ are also occasionally used.
An EC meter is normally used to measure conductivity in a solution.