Lithium Ion Single Cell Voltage

A single lithium ion cell is often the battery of choice for portable equipment because of its high energy density.

Lithium ion single cell voltage.

Lithium iron phosphate technology has the flattest discharge curve which makes it very difficult to estimate soc on a simple voltage measurement. Lifepo4 and limnnio4 cell still are in developing. The 3 70v cell rating also creates unfamiliar references of 11 1v and 14 8v when connecting. The nominal voltage of lithium ion is 3 60v cell.

Exceeding this voltage range results in premature aging and in safety risks due to the reactive components in the cells. This offers a marketing advantage because the higher voltage boosts the watt hours on paper voltage multiplied by current equals watts. Please see the table below to see advantage and disadvantage of each type cell. The lithium battery output voltage varies during discharging.

For li ion cells they should not be discharged below 2 5v and it s even better if the minimum cell voltage is limited to 3 volts. The 3v to 4 1v provided by a lithium ion cell is also a good match for modern low voltage circuits often simplifying the power supply. The nominal voltage is measured at the mid point between full charged and fully discharged based on a 0 2c discharge where c is the rated capacity of the cell in mah. Some cell manufacturers mark their li ion as 3 70v cell or higher.

There are three types of li ion cells on current market based on chemistry of cathode materials. The drawbacks are the need for protection circuits to prevent abuse as well as high price. What this means is that the maximum voltage of the cell is 4 2v and that the nominal average voltage is 3 7v as the battery is used the voltage will drop lower and lower until the minimum which. Types of lithium ion batteries.

The nominal cell voltage of 3 60v can directly power mobile phones tablets and digital cameras offering simplifications and cost reductions over multi cell designs. Depending on the design and chemistry of your lithium cell you may see them sold under different nominal voltages. For example almost all lithium polymer batteries are 3 7v or 4 2v batteries. However lithium ion batteries have a much flatter discharge curve which means that over a wide operating range the voltage at the battery terminals changes very slightly.

The loss of capacity resulting from the higher cutoff voltage is small because lithium cell voltage drops very quickly when it reaches the discharge limit.