Nickel Cadmium Batteries vs Lithium Ion Batteries

Electrochemistry Analysis of Nickel Cadmium Battery and Lithium Ion Battery

Your average nickel cadmium (NiCad) battery uses cadmium for the negative terminal, nickel oxyhydroxide for the positive terminal and aqueous potassium hydroxide as the electrolyte.

A lithium ion (Li-ion) battery uses graphite as the negative terminal, lithium oxide for the positive terminal and a lithium salt as the electrolyte. Lithium ions move from the negative electrode to the positive electrode during each discharge, and back again when charging.

While nickel cadmium batteries are consumables that need replacing their counterparts the lithium ion batteries are rechargeable and don’t suffer from the same memory loss or discharge that nickel cadmium batteries do; they require less maintenance overall and are environmentally better suited.

Environmental Impact of a Nickel Cadmium Battery and a Lithium Ion Battery

Nickel cadmium batteries typically contain between 6% (industrial batteries) and 18% (consumer batteries) cadmium, which is a very toxic heavy metal and always requires special care during battery disposal. It is considered a toxic waste material and hazardous to the environment. This makes nickel cadmium batteries highly consumable constantly needing to be replaced and disposed of in the correct manner. Nickel cadmium batteries unfortunately always suffer from a “memory effect.” The battery remembers the point in their charge cycle where recharging began. During subsequent uses, voltage will drop at that point as if it had been discharged, this is obviously a major drawback for long term use.

The components of lithium ion batteries are environmentally safe as lithium is nonhazardous waste. The batteries require little maintenance and are environmentally safer and have less of an environmental impact. Lithium ion batteries have little to no self-discharge allowing them to be stored unaffected for months without losing charge, where this is not the case for nickel cadmium batteries.  Lithium ion batteries differ from nickel cadmium batteries in the fact that they are low maintenance and they don’t suffer from the “memory effect” at all and not to mention that they tolerate a wider range of temperatures than their nickel cadmium battery counterparts.

Application Comparison of Nickel Cadmium Battery and Lithium Ion Battery

Nickel cadmium batteries are bigger consumables that will need to be replaced having a limited lifespan, and they suffer from a memory loss and discharge. They have a low energy density and they are more likely to fail and much worse for the environment than lithium ion batteries.  They are considered hazardous waste and require a more costly disposal method.  Physically they will be found to be heavier and larger than lithium ion batteries. Other problems that can occur are a voltage depression or the lazy battery effect where the battery will show that it is fully charged but after one brief use it is quickly discharged leaving the battery fairly useless and it usually occurs due to overcharging, reverse charging that occurs due to user error and can produce potentially dangerous hydrogen gas and finally dendrites can develop over time and they are thin conductive crystals that form inside nickel cadmium batteries and may penetrate the separator membrane between electrodes and can cause internal short circuits and premature failure of the nickel cadmium battery, all of these can mean a reduced battery life of an early and complete failure of the battery.

Lithium ion batteries are physically smaller and lighter than nickel cadmium batteries and can be found in a wider variety of shapes and sizes to meet the needs of the powered object not to mention with a longer life, high energy densities and more storage capability. They are safer for the environment and have less of an impact environmentally than nickel cadmium batteries while operating efficiently at a wider range of temperatures than the counterpart Nickel cadmium batteries.  Lithium ion batteries run for two to three more time when fully charged than nickel cadmium batteries and they charge in about half the time. The only notable drawback of the lithium ion battery is that it can be fragile in construction and placement and often requires a protection circuit to maintain safe operation and long life without maintenance.

Overall while lithium ion batteries may cost more than nickel cadmium batteries it is obvious to see why, the benefits of lithium-ion batteries seriously outweigh the benefits of nickel cadmium batteries. They are all round better performers, last longer with lower maintenance costs and environmentally are the right choice to make. More and more of our technology is being switched for better and brighter lithium ion batteries and nickel cadmium batteries are being retired. Cordless tools are one example that shows this to be true with more and more products making the switch.  They are now the most popular battery choice in all consumer electronics and are showing serious growth in fields such asspecial applications, new improved electric vehicles and a wide range of military applications.  Lithium ion batteries are the fastest growing battery system and it's not hard to see why.