A Gel Cell battery contains acid in a gel form. This acid is free-floating in its container. The main advantage of the gel cell battery is that the gel is not in liquid form so a cracked gel cell does not leak. The gel maintains its semi-solid consistency. The gel cell is similar to the Absorbed Glass Matt battery (AGM) style because the electrolyte is suspended, but different because technically the AGM battery is still considered to be a wet cell. The electrolyte in a gel cell has a silica additive that causes it to set up or stiffen. The recharge voltages on this type of cell are lower than the other styles of lead acid battery. This is probably the most sensitive cell in terms of adverse reactions to over-voltage charging. Gel Batteries are best used in very deep cycle application and may last a bit longer in hot weather applications. If the incorrect battery charger is used on a Gel Cell battery, poor performance and premature failure is certain.