Design of a Programmable Battery Testing Equipment for Lithium-ion Batteries for CEDAT Laboratories
Abstract
In recent years, batteries have become a very important part of our lives. They provide power for the portable electronic devices that we use every day. For example, mobile phones, laptops, watches, electric cars among others. Lithium-ion batteries make up majority of the market as they have a high energy density and low self-discharge.
Battery testing is essential to determine the remaining battery lifetime at different operating conditions. The college lacks testing equipment that can be used by students and researchers at organisations like netlabs!UG, iLabs and Arms that use lithium-ion batteries in their projects. The testing equipment can help them determine the remaining battery lifetime and also rule out a battery as a source of problems when troubleshooting their projects. Given the emergence of locally manufactured electric cars and the use of lithium-ion batteries in solar applications, there is a need for smart charging and testing infrastructure. We believe this research can also contribute greatly to that cause.
We designed a programmable battery testing equipment which involved designing a programmable electronic load and a charging circuit that connected to a hardware/software interface.
We carried out tests and were able to determine state of charge and the equipment can also be used to determine the capacity of a given battery with the right configuration. However, the circuit has a limit of 1 A of current that can be drawn from the battery and can be improved by using a Kalman filter to get a better SoC estimate.