Lithium-ion battery is not the same lithium-ion battery

Until recently, mobile devices with strong currents need – such as power tools and medical equipment – rely on nickel-cadmium and nickel metal hydride batteries. With advances in lithium-based batteries as they apply in relation to the nickel-based batteries in terms of load capacity to be equivalent or even better. It is expected that lithium-based batteries will prevail in these high-current applications.

The cobalt-based lithium-ion was first introduced in 1991 by Sony. Because of their high energy density, continued this battery chemistry by very quickly. The spinel-based lithium-ion had a slower start, probably because of its lower energy density. Upon his release in 1996 called for the operator, especially longer terms. Since many mobile devices today require high current, lithium is now at the front and is enjoying strong demand. This has become even so large that the manufacturers of these batteries can not meet her. Therefore, there is so little advertising for that Dell Latitude D400 battery
type. E-One Moli Energy (Canada) is a leading manufacturer of spinel lithium-ion batteries of cylindrical shape. The company has specialized in the cell styles 18650 and 26700th Other major producers of spinel lithium-ion batteries are Sanyo, Panasonic and Sony.

Sony focuses on the design with nickel, cobalt and manganese (NKM). Nickel, cobalt and manganese are Mehrmetalloxid as the crystalline structure of the cathode to the lithium is added. Within this type of battery, the Dell xps m1730 battery manufacturers offer a wide range of high energy density or high load capacity. These two properties can not be readily combined in a battery, but it must always be a trade. NKM can to 4.10 V / cell load, 100 mV less than cobalt and spinel-based lithium-types. A change in battery chemistry in order to raise the voltage to 4.20 V / cell would, but to a higher capacity, but also lead to a shortening of the cycle life. Instead of the normal 800 cycles to be achieved in a laboratory environment, the cycle number would drop to about 300.

Cathode with phosphate nanoparticles

The newest member of the family, the A123 lithium-ion system, adds to the nano-phosphate to the cathode. Although the manufacturer nor the metal used to keep secret, it is generally accepted that it is iron. The manufacturer specifies that this guy has in all commercially available lithium-ion battery has the highest energy density. The cell can be continuously at a current strength of 35 C discharged to zero (discharge) and tolerates Entladestromimpulse of up to 100 C. The phosphate-based battery has a nominal voltage of about 3.25 V / cell. The landing threshold voltage is at 3.60 V. This cell voltage is much lower than 4,20 V / cell of the cobalt-based lithium-ion batteries – the A123 system needs an appropriate charger. For this Dell Latitude E6400 battery type is a large demand is expected. The company A123 Systems was founded in 2001, among others, Motorola, Qualcomm and MIT was founded.

A mess of tension

Only about ten years, the nominal voltage of a lithium ion cell 3.60 V. An appropriate value because it corresponds to the nominal voltage of three cells connected in series, nickel (1.2 V). A higher cell voltage of Li-Ion brings a handsome Wh value on paper and therefore a marketing advantage with it, the device manufacturer, the cells still see as a 3.60-V cells.

The rated voltage of a lithium-ion batteries is determined by one with about 4,20 V fully charged Dell Latitude E5500 battery is discharged with a current of 0.5 C to 3.00 V, while the average voltage is measured. Due to lower internal resistance is the average voltage of a spinel Li-Ion batteries are higher than that of a cobalt-based batteries. Pure spinel has the lowest internal resistance and a rated voltage of 3.80 V / cell. The exception again is the phosphate-based lithium battery. This type differs most from conventional lithium-ion type.