The global market for Consumer Batteries is projected to reach US$50 billion by 2025, driven by the growing indispensability of batteries in the digital era of laptops, smartphones, tablets, smart electronic wearables and digital cameras. As the most important portable power source, batteries are omnipresent in virtually every sector that utilizes electronic/electrical equipment.

The global battery market is about $50 billion US,of which roughly $5.5 billion is allocated to rechargeable (secondary) batteries.The growth is estimated at 6% annually through 2006.China,India,Brazil,the Czech Republic and South Korea will record some of the strongest market gains.The Freedonia Group,Inc.predicts a US demand of primary and secondary batteries of $US 14 billion by the year 2007.A new generation of energy-hungry electronic devices,such as digital cameras,camera phones and high performance portable computing devices,will drive the growth.Figure 1 projects the consumption of secondary and primary battery in the USA to the year 2012.

Alkaline will dominate the primary battery market.Others primary batteries will be lithium and zinc-air.Primary batteries can be stored up to 10 years and have much higher energy densities than secondary batteries.Figure 2 compares the predicted use of primary alkaline with other chemistries.

Lead-acid will account for half the demand of rechargeables.This battery is mainly used for automotive and stand-by applications.Because of low cost and dependable service in adverse environmental conditions,lead-acid will enjoy a steady increase through to the year 2012.Lithium-based batteries or lithium battery may start to take over some lead-acid applications if the price can be lowered and the service life prolonged.The demand for lead acid batteries is governed by vehicle production.Battery replacements have decreased as new technologies have extended battery life by 6 months.

With the switch to electronic braking and steering by wire in upscale cars,the 3kW capability of the single 12-volt battery will no longer be sufficient,ushering in the 42-volt system.Two 12-volt batteries may be the interim solution.Hybrid vehicles require a high voltage battery of about 150V,which is currently provided by connecting nickel-metal-hydride cells in series.Battery manufacturers are asked to provide a 8-10-year warranty to ensure that the battery will last for the life of the car.A replacement of the main battery would cost as much as installing a new motor.

Lithium-ion will lead the demand in powering portable devices.The market for nickel-cadmium,on the other hand,is shrinking.This chemistry will be replaced with nickel-metal-hydride.Nickel-cadmium still holds a major share for power tools,two-way radios and medical devices.This chemistry is preferred over nickel-metal-hydride for its high durability and reliable service but some countries will ban its use by 2006 for environmental reasons.Exceptions will be made if the substitute is unsuitable.

Little excitement is in store for alternative rechargeable batteries.If the predictions are correct,new chemistries will make up less than 7% of all secondary batteries.With no major breakthrough,the fuel cell will play an insignificant role in providing power for future applications.Cost,size and performance are the main obstacles.Although continuous in operation by replacing fuel capsules,the fuel cell,as we know it today,still needs a backup battery to satisfy the power requirements of modern portable equipment.By the look of things,the electro-chemical battery may keep its present position for some time to come.This puts the miracle battery to the back burner,a battery was supposed to power a laptop for days and enable heated clothing for North Pole expeditions.

Where will commercial batteries come from?

The battery industry is becoming consolidated;competition will remain intense.The top Japanese suppliers held 80% of the market last year,but new contenders from other countries in Asia are making strong in-roads.BYD Battery Co. Ltd. in China is an example of a major new global battery producer.LG Electronics Inc.and Samsung Electronics Co.Ltd. in South Korea are following.These companies are gaining ground due to low pricing and improving quality.

The price of lithium-ion batteries has dropped by 20-50% during the last few years.This prompts established battery manufacturers to shift production to lower-cost regions such as China.Nickel-cadmium and ni-mh battery is not immune to price declines.Prices have dropped by 10-20%.The USA and Europe will continue to produce specialty batteries,mainly used for defense and industrial applications.In comparison to the mass-produced batteries from Asia,American and European packs will be more expensive.

The reusable alkaline was introduced in 1992 as an alternative to disposable batteries.The battery was promoted as a low-cost power source for consumer goods.Attempts were made to open markets for wireless communications,medical and defense.But the big breakthrough never came.Today,the reusable alkaline occupies only a small market and its use is limited to portable entertainment devices and flashlights.The lack of market appeal is regrettable when considering the environmental benefit of having to discard fewer batteries.It is said that the manufacturing cost of the reusable alkaline is only marginally higher than the primary cell or primary battery.

The reusable alkaline battery is inexpensive to buy but the cost per cycle is high when compared to other rechargeable batteries.Whereas nickel-cadmium checks in at $0.04US per cycle based on 1500 cycles,the reusable alkaline costs $0.50 based on 10 full discharge cycles.For many applications,this seemingly high cost is still economical when compared to primary alkaline that provides a one-time use.By only partially discharging the reusable alkaline,an improved cycle life is possible.At 50% depth of discharge,50 cycles can be expected.

The idea of recharging alkaline batteries is not new.Although not endorsed by manufacturers,ordinary alkaline batteries have been recharged in households for many years.Recharging these batteries is only effective,however,if the cells have been discharged to less than 50% of their total capacity.The number of recharges depends solely on the depth of discharge and is limited to a few cycles at best.With each recharge,the amount of capacity the cell can hold is reduced.There is a cautionary advisory.Charging ordinary alkaline batteries may generate hydrogen gas,which can lead to explosion.It is not prudent to charge ordinary alkaline unsupervised.

To compare the operating cost between the standard and reusable alkaline,a study was done on flashlight batteries for hospital use.The reusable alkaline achieved measurable cost savings in the low?intensity care unit in which the flashlights were used only occasionally.The high-intensity care unit,which used the flashlights constantly,did not attain the same result.Deeper discharge and more frequent recharge reduced the service life and offset any cost advantage over the standard alkaline battery.

The reusable alkaline is designed for repeated recharge.Also here,there is a loss of charge acceptance with each recharge.The longevity of the reusable alkaline is a direct function of the depth of discharge;the deeper the discharge,the fewer cycles the battery can endure.Tests performed by Cadex on 'AA' reusable alkaline cells showed a high capacity reading on the first discharge.In fact,the energy density was similar to that of nickel-metal-hydride or ni-mh battery.After the battery was fully discharged and recharged using the manufacturer's charger,the reusable alkaline settled at 60%,a capacity slightly below that of nickel-cadmium.

Repeat cycling in the same manner resulted in a fractional capacity loss with each cycle.The discharge current in the tests was adjusted to 200mA;the end-of-discharge threshold was set to 1V/cell.An additional limitation of the reusable alkaline system is its high internal resistance,resulting in a load current capability of only 400mA.Although adequate for portable radios receivers,CD players,tape players and flashlights,400mA is insufficient to power most mobile phones and video cameras.When considering reusable alkaline,one must realize that the initial energy is slightly lower than that of the standard alkaline.Cost savings are realized if the batteries are never fully discharged but have a change to be recharged often.

Advantages

Inexpensive-can be used as a direct replacement for non-rechargeable (primary) cells.

More economical than non-rechargeables-allows several recharges.

Low self-discharge-can be stored as a standby battery for up to 10 years.

Environmentally friendly-no toxic metals used,fewer batteries are discarded.

Maintenance free-no need for cycling; no memory.

Limitations

Limited current handling-suited for light-duty applications like portable home entertainment,flashlights.

Limited cycle life-for best results,recharge before the battery gets too low.