HOW TO CHOOSE YOUR LITHIUM-ION BATTERY

Updated: Aug 24, 2020

Lithium-ion battery or Li-ion battery (abbreviated as LIB) is a type of rechargeable battery. Lithium-ion batteries are commonly used for portable electronics and electric vehicles and are growing in popularity for military and aerospace applications.

A battery or battery pack is a collection of cells or cell assemblies, with housing, electrical connections, and possibly electronics for control and protection. In the batteries, lithium ions move from the negative electrode through an electrolyte to the positive electrode during discharge, and back when charging. Li-ion batteries use an intercalated lithium compound as the material at the positive electrode and typically graphite at the negative electrode. The batteries have a high energy density, no memory effect (other than LFP cells) and low self-discharge.

TYPES OF LITHIUM-ION BATTERIES

Lithium Ferro Phosphate (LFP) - LFP Batteries are a good replacement to Lead-acid batteries. Because of the nominal 3.2 V output, four cells can be placed in series for a nominal voltage of 12.8 V. LFP batteries for solar applications have a long life typically guaranteed for 5 years.

Nickel Cadmium Manganese (NCM) - These Lithium-ion batteries provide lightweight, high energy density power sources for a variety of devices. Lithium ion cells come in 3 different sizes namely 18650, 26650 and 32650. These are cylindrical cells with varying diameter and fixed height of 65 mm. The capacity of the cells vary according to the size. The life cycle of the cells also varies according to the size. Lithium Ion cells have a wide ranging life cycle starting from 500 cycles going up to 1500 cycles.

Lithium Titanium Oxide (LTO) – LTO is a highly safe rechargeable battery with six outstanding characteristics. LTO cells are having a nominal a cell voltage of 2.40V, it releases a high current discharge current that is 10 times the capacity of the other types of lithium batteries. LTO has long life exceeding 20,000 charge/discharge cycles and a rapid charging time of 6 minutes.

CELL

Cell is a single unit that converts chemical energy into electrical energy. A cell refers to a single anode and cathode separated by electrolyte used to produce a voltage and current. A battery is a combination of one or more cells. A single AA battery, for example, is one cell.

Cell of a Lithium-Ion battery has following dimensions.

18,650 or 18 mm Diameter

21,650 or 21 mm Diameter

32,650 or 32 mm Diameter

Explanation

There are 2 required parameters for a battery.

Voltage (V) – Voltage is the pressure from an electrical circuit's power source that pushes charged electrons (current) through a conducting loop, enabling them to do work such as illuminating a light. In brief, voltage = pressure, and it is measured in volts (V).

Ampere Hour (Ah) – Ampere Hour is the unit of electric charge, having dimensions of electric current multiply by time, equal to the charge transferred by a steady current of one ampere flowing for one hour.

Battery-wise Voltage and Ampere Hour explanation.

LFP
- Cell voltage capacity – 3.2 V
- Cell Ah capacity – 3Ah, 4Ah and 6.3Ah
NCM
- Cell Voltage Capacity – 3.7 V
- Cell Ah capacity – 3Ah, 4Ah and 6/6.3Ah
LTO
- Cell Voltage capacity – 2.3V
- Cell Ah capacity – 20Ah, 30Ah and 40Ah

BATTERY

Battery is a combination of one or more cells with external connections for powering electrical devices. When a battery is supplying electric power, its positive terminal is the cathode and its negative terminal is the anode.

Cells are placed in series and parallel to form a battery.