The jelly roll or Swiss roll design is the design used in the majority of cylindrical

rechargeable batteries A rechargeable battery, storage battery, or secondary cell (formally a type of energy accumulator), is a type of electrical battery which can be charged, discharged into a load, and recharged many times, as opposed to a disposable or prima ...

, including nickel–cadmium (Ni-Cd), nickel-metal hydride (Ni-MH), and

lithium-ion A lithium-ion or Li-ion battery is a type of rechargeable battery which uses the reversible reduction of lithium ions to store energy. It is the predominant battery type used in portable consumer electronics and electric vehicles. It also ...

(Li-ion). The design has this name because the cross section of the battery looks like a

Swiss roll A Swiss roll, jelly roll (United States), roll cake, cream roll, roulade or Swiss log is a type of rolled sponge cake filled with whipped cream, jam, or icing. The origins of the term are unclear; in spite of the name "Swiss roll", the cake i ...

. In this design, an insulating sheet is laid down, then a thin layer of an

anode An anode is an electrode of a polarized electrical device through which conventional current enters the device. This contrasts with a cathode, an electrode of the device through which conventional current leaves the device. A common mnemonic is ...

material is laid down, a separator layer is applied, and a

cathode A cathode is the electrode from which a conventional current leaves a polarized electrical device. This definition can be recalled by using the mnemonic ''CCD'' for ''Cathode Current Departs''. A conventional current describes the direction in whi ...

material is layered on top. This sandwich is then rolled up and inserted into a hollow cylinder casing. The battery is sealed, metal contacts are attached, and an optional button top is applied if the battery is intended to replace an AAA/AA/C/D

alkaline battery An alkaline battery (IEC code: L) is a type of primary battery where the electrolyte (most commonly potassium hydroxide) has a pH value above 7. Typically these batteries derive energy from the reaction between zinc metal and manganese dioxide, ...

. A label with the brand name is then applied, or a blank protective label, often green (for Ni-MH) or blue (for Ni-Cd) for a generic or OEM battery. Occasionally, the design is also used for

primary Primary or primaries may refer to: Arts, entertainment, and media Music Groups and labels * Primary (band), from Australia * Primary (musician), hip hop musician and record producer from South Korea * Primary Music, Israeli record label Works ...

(non-rechargeable) batteries, although most primary batteries use the conventional rod-paste-tube design.

References

{{Reflist Rechargeable batteries