Degradation of the battery of your portable electronic gadgets or equipments

Almost all portable electronics equipment or gadgets (such as laptops, ipads and cell phones) produced now days use rechargeable batteries referred to as lithium-ion batteries (LIB). Lithium-ion batteries as the name suggests, discharges by moving lithium ions from the negative to the positive electrodes and vice versa for charging.   The shift to lithium ion batteries is due to high energy density, high voltages per cell, and better charging/discharging characteristics among other advantages.

Although these batteries have good performance, they degrade and the rate of degradation is dependent on conditions of operation and how they are handled by the users.

I did a small experiment with my laptop battery by monitoring the capacity of the battery during a 10 month period. The results indicated that the capacity of the battery had reduced by 33%. The battery used to discharge in 165 minutes in October 2010 but the time reduced to 110 minutes in July 2011. This means if the rate of degradation remains constant, the battery has a lifetime of about 3 years and can only meet the expectation of the user for about one year (assuming the standby time is at least 2 hours). The graph below illustrates the results. Note that the results have been fitted linearly for demonstration purposes. The characteristics are not linear in a real situation.

Some of the factors that enhance the degradation of the battery include:

·         Overcharging

·         Deep discharging

·         Overheating of the battery

·         Defective battery charger (for instance may provide high voltages to the battery)

It is important to note that the battery degrades even if is not in use. So do not underutilize your battery. Also the rate of discharge depends on the intensity of the gadget use. However, some tips to lengthen the life of your gadget’s battery include but not limited to:

·         Avoid overcharging the battery (for instance by leaving it charging overnight)

·         Avoid deep discharging the battery i.e. do not use the battery until it is completely empty.

·         If the gadget has a battery management system, e.g. laptop:

o       Ensure that low battery limit is 20% to avoid deep discharge

o       Optimise you gadget use (e.g. by hibernating it when not in use, dimming the display e.t.c)

·         Make sure the battery is not overheated. For instance, a fan under the laptop may save you a great deal.

·         Regularly check you battery charger to ensure that it is not defective and that the rated specifications (e.g. voltage) are correct and not exceed.

Take care of your battery and it will serve you better!!