The invention and development of the battery is expected to be one of the most important in human history. Without batteries, the world would be very different. Everything would be plugged in and nothing would be mobile. There are many types of batteries that work in different ways, but they all have the same common goal: to make life easier. Some examples of these batteries are lithium-ion, lead-acid, and nickel-cadmium. Lithium-ion batteries are the most accepted batteries for portable equipment such as laptops and cell phones. The density of these batteries is normally twice that of nickel-cadmium, making them more desirable for portable devices. The chemistry of these batteries is better for the environment because they cause virtually no harm when disposed of. The advantages of these batteries are that they have high energy density and can be further improved for future applications. This type of battery does not need to be “primed” for the first few uses compared to other batteries. Additionally, it has very low self-discharge, meaning the battery can retain its charge for extended periods of time. In addition, compared to other batteries, it can provide higher current to power tools and more constant power output, until the battery is almost empty. This battery has some limitations such as circuit protection to maintain voltage and current levels. Additionally, when this battery is not used, it continues to age. It has a limited number of life cycles until the battery begins to lose capacity. Lithium-ion batteries are also more expensive to manufacture than other batteries on the market. Overall, the advantages of lithium-ion batteries outweigh the disadvantages, making them an excellent candidate...... middle of paper... ...t. This effect is often observed when a battery is recharged before being completely discharged. Over time, this cycle causes the battery to “memorize” the lower energy capacity, resulting in an incomplete charge. This effect comes into play when a battery is discharged to the same point repeatedly and then recharged. This causes a chemical difference between the active and inactive layers of the conductive material. This results in reduced battery life at the time the cell is usually recharged. In conclusion, the best type of battery varies depending on the situation. For example, lithium-ion cells are better suited for cell phones, while lead-acid cells are better suited for automobiles. Each type of battery has its own advantages and disadvantages, so sacrifices must be made. The battery chosen will depend on the specifications and design requirements.