Lithium Batteries vs. Alkaline Batteries
You might say batteries are the core element that keeps the world mobile. Most portable products, from the smartphone in your pocket to the car in your driveway, rely in some way on battery power.
The essential need for batteries combined with their potential environmental impact has forced manufacturers to provide solutions. Modern non-toxic alkaline batteries are one option available to replace the more dangerous older alkaline varieties that were laden with mercury and other types of heavy metal or lithium products with perchlorate. To understand why this evolution matters, you must know more about each type.
Batteries are often defined by the chemical process that makes them work. Alkaline, or alkaline manganese, batteries account for most of the marketplace, approximately 80 percent, according to Enterprise Risk Management (ERM). These are the AA or AAA batteries you put into toys, cameras and radios. They also come in a button variety for smaller electronics like a hearing aid.
Prior to 1996, alkaline batteries contained mercury. This made them especially toxic when disposed of in landfills. The heavy metals and corrosive chemicals pollute the soil and ground water.
The laws regarding alkaline battery disposal vary by location. Some states allow newer products to be thrown away normally. Others maintain tight control over waste batteries, assuming incorrectly that all alkaline products are hazardous.
Given the potential environmental risks associate with heavy metals, manufacturers developed a button battery product able to produce even more energy utilizing zinc, but without the heavy metal components.
Button alkaline batteries meet both the US and EU standards, but the regulations for disposal vary from location to location.
In the 1970s, lithium batteries hit the market for use in portable electronic devices. This battery style is more compact than the alkaline design, making it a practical choice for things like cell phones and PDAs.
Lithium battery is an umbrella term for a number of different type batteries that use cathodes and electrolytes to function. Lithium is the common ingredient in all of them. They will contain at least .15 kg of lithium per kWh.
The chemistries of the different types will vary. For example, a metallic lithium battery, which is the most common, applies lithium as anode and manganese dioxide as cathode and uses an organic solvent as a dissolving agent. These are the lithium batteries you see in consumer products.
There are lithium batteries specific to commercial applications, as well, such as a wireless alarm system. This lithium product has a large energy density. It contains thionyl chloride and lithium tetrachloroaluminate, as well as a carbon cathode current collector.
The biggest problem with lithium batteries is their environmental impact. While, this style contains no toxic elements like lead, mercury or cadmium, it does offer disposal challenges. To classify something as hazardous waste, it must meet at least one of four criteria.
Corrosion is a common concern with lithium products, especially the button style that contains SO2 and thionyl chloride. These are used in electronics like cameras or watches.
It is necessary to fully discharge a lithium battery prior to disposal. A partially discharged battery may explode if it short-circuits. Manufacturers call this decrimpling – the build up of internal pressure inside the battery until it ruptures.
Button-sized batteries contain lithium perchlorate as an electrolyte. Perchlorates become explosive when they mix with organic compounds. Lithium batteries are deemed hazardous waste in many regions including California.
Lithium vs. Alkaline
The choice of battery depends on the device, but there are significant advantages to alkaline products.
- Button-sized alkaline batteries contain no heavy metals that pollute the ground water or soil
- Button-sized alkaline batteries do not explode in landfills
- Alkaline batteries are cost-effective
- Alkaline provide high energy levels
Lithium batteries are not without their benefits; however, they tend to be less advantageous, especially to the environment.
- Lithium batteries must be fully discharged prior to disposal.
- Lithium batteries contain perchlorate, which, when mixed with organic material, may explode.
The environmental factors make them the less positive power choice. The Environmental Protection Agency warns these products are hazardous waste if improperly disposed of.
In landfills, the batteries break open and deposit harmful compounds into the soil and release toxins into the air. Once, exposed, the metals end up in ground and surface water. Some plants take the metals up from the earth to expose animals and humans to toxic materials. When placed in incinerators incorrectly, they release metals into the air that collect in the ash produced by combustion.
This can lead to:
- Excessive salivation
- Abdominal pain
- Liver damage
- Kidney damage
- Skin rashes
- Chronic anxiety
- Developmental issues in children
Gas produced by the landfills is a contributing factor to global climate changes, as well.
Reclamation companies break these batteries down to utilize their materials, but it is a costly process with little value other than to keep the batteries out of landfills.
The battery industry is growing and evolving all the time. Alkaline and lithium are just two players in an extensive list of battery options. For the environment, however, the button-sized alkaline batteries with no heavy metals make less of an impact.