What are dealing with?

There are a number of different types of household batteries used by householders for a variety of purposes.  The three main types are:

Wet-cell: Lead acid batteries used to power vehicles and by industry. 

Dry-cell non-rechargeable: These are the most common types of household battery. 

General purpose disposable household batteries include:

• Zinc carbon used in low drainage appliances such as torches, clocks, shavers and radios.
• Zinc chloride used in similar applications.
• Alkaline manganese used in personal stereos, radio-cassette players. Less prone to leaking than the above two types and longer lasting. 
• Primary button cells:
  • Mercuric oxide used in batteries for hearing aids, pacemakers, photographic equipment.
  • Zinc air - an alternative to mercuric oxide button cells - used for hearing aids and radio pagers.
  • Silver oxide used for electronic watches and calculators.
  • Lithium used for watches and photographic equipment.

Dry-cell rechargeable - general purpose rechargeable batteries for the above uses, and also including Nickel cadmium, Nickel metal hydride and Lithium-Ion batteries used in power tools, cordless appliances, mobile phones etc.

• Nickel cadmium (NiCd) batteries represent one of the fastest growing sectors in the battery market.  Used for cordless power tools, personal stereos, portable telephones, lap-top computers, shavers, motorised toys etc, with a life of 4-5 years. 
• Nickel metal hydride (NiMH) batteries are a less environmentally harmful alternative to NiCd and tend to have a longer life.
• Lithium ion (Li-Ion) batteries have a greater energy storage capacity than NiCd and NiMH batteries.

Using rechargeable batteries reduces the number of batteries requiring disposal, but 80% of them contain nickel cadmium, a known human carcinogen, and therefore need to be disposed of safely.

Why should we recycle Batteries?

It is estimated that in 2000, almost 19,000 tonnes of waste general purpose batteries and 113,000 tonnes of waste automotive batteries required disposal in the UK.  

Currently, only a very small percentage of consumer disposable batteries are recycled (less than 2%) and most waste batteries are disposed of in landfill sites. The rate for recycling of consumer rechargeable batteries is estimated to be 5%. 

All waste batteries are classified as hazardous waste and recycling is always the best option.

Ordinary household batteries do contain some hazardous chemicals so ideally should not be thrown out with the day to day rubbish.

Rechargeable batteries contain harmful metals, so should never be thrown away with daily rubbish, they should be returned to manufacturer for disposal or recycled elsewhere.When disposed of incorrectly, these heavy metals may leak into the ground when the battery casing corrodes.  This can contribute to soil and water pollution and endanger wildlife. Cadmium, for example, can be toxic to aquatic invertebrates and can bio-accumulate in fish, which damages ecosystems and makes them unfit for human consumption. Some batteries, such as button cell batteries, also contain mercury, which has similarly hazardous properties.

How are Batteries recycled?

Lead can be recovered by either separating the different materials that make up the battery (lead, plastics, acid, etc.) prior to metallurgical processing. Alternatively, batteries can be processed as a whole through heat treatment in a particular type of furnace with metals being recovered at the end of his process.

NiCd batteries can be reprocessed through a similar thermal technique, which recovers cadmium and iron-nickel for steel production.

Batteries containing mercury (button cells) are most commonly processed using a vacuum-thermal treatment, in which the mercury vaporises. It condenses and eventually solidifies when temperatures are reduced and can then be reintroduced into the material cycle.

NiMH batteries are reprocessed by mechanically separating the individual materials (plastic, hydrogen and nickel) within a vacuum chamber to prevent the escape of hydrogen. The output of this process is a product with high nickel content which can be used in the manufacture of stainless steel.

Li-Ion batteries are currently reprocessed through pyrolysis (heat treatment) with the primary recovery the metal content.

Zinc-carbon/air and alkaline-manganese batteries can be reprocessed using a number of different methods, which include smelting and other thermal-metallurgical processes to recover the metal content (particularly zinc).

How you can help

Use the mains when possible.

Use rechargeable batteries and a battery charger. This saves energy because the energy needed to manufacture a battery is on average 50 times greater than the energy it gives out. However, rechargeable batteries are not suitable for smoke alarms as they tend to run out suddenly, preventing the alarm from warning when battery power is low.

Opt for appliances that can use power derived from the sun via solar panels or from a winding mechanism, e.g. radios, mobile phone wind-up chargers.

Participate in local authority battery collection schemes where they are available. If you Council does not provide one at the moment, contact them and find out if they are planning to do so in future.

Seek guidance on how to dispose or recycle batteries from either the distributor who originally supplied the battery, the battery manufacturer or the appliance manufacturer.

Send batteries back to manufacturers for recycling or reprocessing where such a scheme is available.