A basic comparison of Lead-Acid batteries to Lithium Batteries

A basic comparison of Lead-Acid batteries to Lithium Batteries

This article is not a scientific paper targeted to chemistry or electric researchers. It is intended as an introduction for potential users or even to the interested public community. If somebody should get more interested in that technology through this article: at the end of this Article there are a number of links which lead much deeper into this technology.

Undoubtedly Lithium Energy Storage Technology will have a great future. The actual standard already enabled the electronic device industry to develop products which ten years ago where unimaginable. The rise of Apple like the Phoenix out of the ashes was only able after products like the iPod where able to be developed due to miniaturized and stable battery technology. Apple is only an example. Others like Google, Blackberry and Samsung owe a large portion of their revenues the interesting Chemistry of Lithium – Ion Technology they use in their products.

But new materials will be found. The Lithium research is worldwide a top theme. Better electrodes will be developed, Battery housing materials and separating membranes will improve. The chemistry of the electrolytes and media will be fine-tuned with supporting catalysts. It is in reach that battery driven cars will go distances further as their gasoline driven ancestors and an exchange of a Lithium – Ion battery will be shorter than pumping the tank full with gasoline.

And we all will see passenger airplanes with sunlight charged Lithium – Ion aggregates crossing the Oceans.

Watching this industry will be profitable for researches, for the industry and for the individual investor.

General Battery chemistry

Most people do not realize that a battery is a miniaturized chemical plant.

Electricity is created through a controlled chemical reaction between different substances.

No matter what battery type we are talking about, Lithium - Ion or lead – acid they mostly have the same components:

An Anode, a cathode and a substance between which serves as an electrolyte.

The Anode normally is the positive pole where electrical current flows to when the battery is in operation.

The cathode is the negative pole and during battery operation current flows out of it.

The chemistry between the poles provides the current with its charge and here comes the third substance into play: the electrolyte which is serving like a medium. Would Anode and Cathode get into direct contact a short circuit would happen and the battery becomes nonfunctional.

The special Chemistry of Lead Acid Batteries

The Anode and Cathode in lead acid battery are made from lead and lead dioxide. The bridging medium in between is a solution of a diluted sulfuric acid.

When the battery discharges electricity, the chemical reaction changes the two electrodes into lead sulfate.

Recharging the battery reverses this reaction.

The special Chemistry of Lithium – Ion Batteries

A variety of substances are used in Lithium – Ion Batteries.

While the battery is producing energy there is a controlled migration of Lithium between the Electrodes.

The Anode is made typically of Graphite while the cathodes could be made out of Lithium Cobalt oxide, Lithium Iron Phosphate or other Lithium based substances. The electrolyte is usually a solution of lithium salt in an organic solvent.

By recharging a Lithium - Ion Battery the migration of lithium is reversed.

Both Battery Types have special Features:

Lead – Acid

While lead acid batteries are one of the oldest battery types already in use in the 19^th century.

Energy to weight and Energy to volume relations are very low so the Batteries are very heavy and big. Big in the relation for the amount of power to be to be stored and put out.

A pro for these type of batteries is that they can deliver a high surge-to-weight ratio meaning they can deliver a high jolt of electricity at once. For applications which need a large sudden surge of power like for starters in cars they are ideal.

Another pro is that Acid – Lead batteries are cheap to produce. When steady low or middling supply is requested over a longer period of time they are not well behaving.

Another disadvantage are long recharging times through the reversal of the slow reactions typical for the lead acid chemistry.

Lithium Ion

Compared with a lead acid battery, Lithium Ion constructions have a high power-to-weight and power-to-volume ratio. Meaning their weight and volume are very small in relation to the power they are putting out.

This power to weight and power to volume ratio make this batteries ideal for today’s electronic devices like cellphones, lap tops, tablet computers and all the other electronic devices gadgets and toys.

The shorter life time of the Lithium Ion devices does, is not a major disadvantage in that industry, as the relatively short lifetime of these batteries is often the same as the lifetime of the one of these devices. Some companies are even put in non-exchangeable Lithium – Ion batteries in their products like laptops or tablet computers to force the users to buy after a few years a newer device, when the battery has given up working. A disadvantage turned to higher output and revenues.

Without the development of Lithium Ion Batteries the triumphal march of the small electronic devices is not imaginable and would have been hardly possible.

Just imagine to have sitting aside your laptop an acid-lead battery or carry the battery separately in your briefcase. Sounds anachronistic? This kind of scenario has being discussed as a possibility to “carry on computers” in the early nineties in computer development before the term “laptop” was ever invented.

So far as it is discussed here, it can be determined that Lithium - Ion batteries have found their place in the modern electronic devices.

But there are more user benefits:

Lithium-ion batteries have a higher density than most batteries, allowing them to store more energy for their size.

The batteries operate at a higher voltage than other rechargeable batteries, which means one cell can be used instead of multiple cells.

Additionally, because lithium-ion batteries hold a charge for a longer period of time, even while not installed in an electronic device, they are more practical than other battery types.

Specialty lithium-ion batteries can provide sufficient very high current to power tools. These batteries have rapid recharge capabilities, no memory effect and broad temperature ranges for operating.

Lithium-Ion batteries are able to maintain a charge for many months.

As a rechargeable battery, lithium-ion batteries are recyclable. Businesses that sell the batteries will also take them back for recycling, according to “Green Batteries”.

As said in the beginning chapter this article can be only a short introduction into a technology which has been emerged quietly and without much publicity.

We might hear not much more in future about breathtaking Lithium – Ion developments.

But we will see cars cruising silently the highways from the Atlantic to the Pacific and airplanes crossing the oceans without destroying the Ozone Layer and you the reader of this article will know: It only was able to happen because new battery developments have progressed further again.

Sources and Links

http://www.batterypoweronline.com/main/wp-content/uploads/2012/07/Lead-acid-white-paper.pdf

http://www.energiespeicher-nds.de/fileadmin/Arbeitskreise/Workshops/speicheranw._Gebaeude-Energiemanagement/Wedigo_Wenzel_Next_Energy_EFZN.pdf

http://www.ehow.com/info_8158723_disadvantages-lead-acid-batteries.html

http://www.ibc-blog.de/2013/09/die-qual-der-wahl-blei-oder-lithium/

http://energiespeicher.blogspot.com/2013/06/lithium-oder-blei-batteriespeicher-ein.html