There is so much you can do with batteries these days and their importance is such that we cannot imagine our life without a use of battery in our daily life. From cars, motorbikes, all kinds of electric vehicles, boats, and even our riding mowers are just a few examples where batteries are required. Batteries are the main source of emergency power in times of failure as well as they are used in all kinds of electrical vehicles.
Those batteries that include an electrolyte and are made of sulphuric acid, water and lead plates are called Lead acid batteries. The most common types of battery are wet cell type and they need regular maintenance by adding water. If you forget to add water regularly, these batteries can dry up and are damaged severely.
Whereas, Gel batteries don't need much maintenance because the sulphuric acid is in gel form. There batteries are sealed with a valve which remove excessive pressure. Because of the gel like substance, there is no risk of leakage and therefore can be placed in any place or position. However the traditional batteries can only be placed in one position which is upright.
Another advantage is that even if the battery breaks, there is no danger of any spill unlike the flooded type batteries. Gel batteries are also resistant to vibration and shock. They don't produce hydrogen fumes so you also don't need to worry about placing them in a special ventilated area while charging them. Being deep cycle batteries they have got a higher discharge feature.
The best feature for me is that a gel battery can be revived even if they are left discharged for some time unlike the wet cell batteries. Another advantage over lead acid battery is that it doesn't develop a memory which reduce battery capacity to recharge.
These batteries can be used in so many different applications, most of all in power wheelchairs, backup for computer, ventilators in a health facility and for solar power electricity storage for emergency lightening. The electric car is the most common example where a gel battery is used. These batteries have also been approved and are being used in public transportation and airlines.
When you compare it with a wet cell type battery, the heavy price tag of a gel battery is considered to be its main drawback. They also require charging at a slower rate as compared to a lead acid battery. You must also stop its charging after the charging is complete because it can develop voids with its electrolyte. The extent of the damage is such that it can't be fixed and as a result it loses its charging capacity. In order to increase the battery's lifespan you need to keep it from heat, as heat affects the saturation with sulphuric acid.
I would recommend using a gel battery because of its long life and low maintenance. You can buy Gel batteries from any local hardware retail store or you can order online as well.