Pouch Cell Battery Pack Design

Engineering guidelines for designing battery packs.

Pouch cell battery pack design.

In 1995 the pouch cell surprised the battery world with a radical new design. A 4s pack of lfp is the most common replacement for a 12v lead acid battery pack 4p x 3 2v 12 8v nominal. With a simple series chain of cells the battery capacity in amphours is the same as the capacity of the individual cells since the current flows equally through all the cells in the chain. The charging path uses low current power switches to save in the overall bom cost of the system.

Or save 1 2 mm of width per cell. For cell battery pack. Rather than using a metallic cylinder and glass to metal electrical feed through for insulation conductive foil tabs welded to the electrode and sealed to the pouch carry the positive and negative terminals to the outside. The electrolyte soaked battery pouch is heat sealed and placed in a vacuum chamber which removes excess air from inside the pouch.

Pouch cell battery packs. The pouch packs are used in consumer military and automotive applications. Figure 7 illustrates a pouch cell. Eliminating the metal enclosure reduces weight but the cell needs support and allowance to expand in the battery compartment.

Battery pack design considerations and construction details. In battery packs with many cells in a series the entire pack can be taken down if a single cell is weak or non operational. 8 channel battery analyzer 0 6 300 ma upto 5v w temperature dcr measurement and laptop software bst8 300 cst. The pouch cell makes most efficient use of space and achieves 90 95 percent packaging efficiency the highest among battery packs.

Rather than using a metallic cylinder and glass to metal electrical feed through conductive foil tabs are welded to the electrodes and brought to the outside in a fully sealed way. See also cell construction. Current ev battery packs are composed of a number of individual modules ganged together to form the. Packing cells in a tube 3 cells.

For a 3 cell pack you can put the cells in a tube the diameter of the outer circle is 2 16 d. However lifepo4 is considered the most fire safe sometimes found as a starter battery on small aircraft and they also typically last about twice as long as the common nca ncm 18650 cell packs. The cell to pack battery design is interesting because of what it eliminates rather than adds. Custom design and manufacture of state of the art battery chargers battery packs ups and power supplies.

To save cost many designs actually use separate contacts for charging and discharging the battery pack. Liquid electrolyte is injected into an open battery pouch. For battery pack cell.