Batteries are temporary power solutions for laptops. They are portable and ergonomically fitted to each system. Therefore, laptop batteries are generally specific to a few models. Recent lithium-based laptop batteries commonly come in six- and nine-cell versions.
A nine-cell lithium battery has a charge capacity which is about 50 percent greater than that of a six-cell battery. Charge potentials for both versions will depreciate at about the same rate under the same conditions.
Nine-cell batteries are always more expensive than six-cell batteries. Price ranges and differences vary widely by battery model.
Over time, charge integrity of laptop batteries decreases. A nine-cell battery has a better chance of being able to hold its charge after a few years of usage because it has additional cells that may not die out. This is assuming that both batteries are created by the same manufacturer.
Nine-cell batteries are much bulkier and tend to protrude from laptop bodies. They cause the laptop to become heavier and lean toward the back. Six-cell batteries blend in with most laptop builds; they are the current industry standard.
The average battery on a consumer laptop is composed of lightweight lithium ion cells. The same material is used for both the six- and nine-cell versions.