Battery Education

The Battery - Cathodes, Anodes, and Electrodes (Part 1 of 2)!

A battery as we know it is a device that stores chemical energy and through an electrochemical process (electromotive force) converts the stored chemical energy into electric energy via a direct current voltage. The chemical conversion is a process of chemical change created by adding or losing chemical substances (electrons, oxygen, lithium etc.) inside the battery and used by a connecting device (i.e. PDA, iPod, Digital Camera).

A battery cell is the most basic electrochemical unit and often time cells are stacked on top of one another to meet a specific energy design or need, however, when we are speaking of battery cells we refer to them as a battery whether there is one cell, three, or more in a series.

Within each battery cell are three basic components: the anode, the cathode, and an electrolyte solution. Just to be clear every battery design does indeed have more components contained in the battery then the three listed above, however, the electrodes and the electrolyte are the very basic components of all batteries. In this 1of 2 article report however we are going to focus specifically on the cathode and the anode, commonly referred to as the electrodes.

Batteries power devices by the creation of direct electrical current drawn from the flow of electrons, flowing back and forth between the electrodes. The basic format is that electrons collect on the negative electrode, when a substance (i.e a wire, an electrolyte) is placed as a separator between the negative electrode and the positive electrode the electrons flow (are drawn) to the positive electrode. This flow creates a current. The electron current, or electricity, can then be directed to a device and used as a power stream.

The reason why electrons flow is part of the atomic design. Electrons spin around the center, or nucleus, of atoms, in the same way the earth spins around the sun. The nucleus is made up of neutrons and protons. Electrons contain a negative charge, protons a positive charge. Neutrons are neutral -- they have neither a positive nor a negative charge.

There are many different kinds of atoms, one for each type of element. An atom is a single part that makes up an element. There are 118 different known elements. The mass accumulation of elements makes up every thing we can see, touch, hear, and smell (elements are even in things we can’t see).

Each atom has a specific number of electrons, protons and neutrons. But no matter how many particles an atom has, the number of electrons usually needs to be the same as the number of protons. If the numbers are the same, the atom is called balanced, and it is very stable.

Some kinds of atoms have loosely attached electrons. An atom that loses electrons has more protons than electrons and is positively charged. An atom that gains electrons has more negative particles and is negatively charge. A "charged" atom is called an "ion."

The very nature of a positive atom is that a positive atom attracts electrons from negative charged atoms to in effect balance the positive atoms. Why, not sure, and for this article not pertinent. What is necessary to know is that the flow of electrons to positive charged atoms is essential for a direct electrical current.

You see electrons can be engineered to move from one atom to another. When those electrons move between the atoms, a current or flow of electricity is created. The electrons move from one atom to another in a "flow." One electron is attached and another electron is lost. This creates a continual equilibrium amongst the atoms.

Engineers manufacture disequilibrium to create free negative electrons so that the positive atoms will attract the electrons at the positive electrode, thereby creating an electron flow or electrical current. When electrons move from atom to atom a current of electricity is created. This is what happens in a piece of wire. The electrons are passed from atom to atom, creating an electrical current from one end to other end.

Inside the battery itself, is a chemical reaction that produces the electrons. If the electrons are not moving then the battery can sit on the shelf for a year. Once the chemical is activated and the flow of electrons takes place, even for a moment then the loss of power begins and there is no stopping it. This is why you never want to buy a used battery.

Until next time -  Dan Hagopian, www.batteryship.com

Lithium Solid Polymer Electrolyte Batteries

If you have ever owned a PDA, iPod or any other small electrical device the battery power more often then not incorporated a technology called lithium polymer. For example take a look at these HP Compaq iPAQ Batteries at http://www.batteryship.com/htmlos/htmlos.cgi/batteryship/catalog.html?search=ipaq&lp=1&pt=HP+Compaq+iPAQ+Batteries.

As you see many of these batteries like many other batteries found at BatteryShip.com incorporate a technology that is absolutely amazing as it is functional. This amazing technology is contained in the electrolyte solution that is the conducting medium of the battery and the enabler of the direct current (where volts come from in the battery) to power your electronic device. What is so amazing about it is that the conducting metal gel which is enabling the current to flow to and from the electrodes is only tens of micrometers wide (that is smaller then one of your strands of hair)!

A battery as we know it is a device that stores chemical energy and through an electrochemical/electromotive force converts the stored chemical energy into electric energy via a direct current voltage. A battery cell is the most basic electrochemical unit. When we speak of battery cells we know them as a battery whether there is one cell or three in a series.

A battery cell has three basic parts: the anode, the cathode, and an electrolyte solution. In this article we are going to focus specifically on the electrolyte.

The electrolyte solution is a chemical compound (salt, acid, or base) that when dissolved in a solvent forms a solution that becomes an ionic conductor of electricity. In the battery cell the electrolyte solution is the conducting medium in which the flow of electric current between the electrodes takes place by the migrating electrons.

Since the 1970 it has been known that adding salts to polymers can enable the polymer to conduct lithium ion. The material thus can serve as an electrolyte in lithium batteries. Lithium solid polymer electrolyte batteries, when given full measure to the capacity for miniaturization of a fully solid state battery can have the highest specific energy and specific power of any rechargeable technology.

Some of the benefits that lithium solid polymer electrolytes offers are:

• ease of manufacturing
• immunity from leakage
• suppression of lithium dendrite formation
• elimination of volatile organic liquids
• mechanical flexibility.

It is in the mechanical flexibility that makes batteries with a lithium solid polymer electrolyte most incredible. The capability of a lithium solid polymer electrolyte to be flexible allows the rechargeable technology to fit in the smallest of systems. With battery designs smaller then a less than half the size of a credit card, the flexibility aspect of the polymer allows the electrolyte to incorporate a multilayer laminate of thin films of metal, polymer, and ceramic, measuring tens of micrometers in thickness (the human hair is about 50 micrometers wide) which can deliver the highest specific energy and specific power of any rechargeable technology of its miniature size.  To understand the how amazing this technology is imagine thin gel like metal smaller then the width of your hair that not only can bend, stretched, and wrapped but can also deliver enough electrical charge to power your iPod, PDA, or Digital Camera and then you will begin to understand the incredible capability of this technology.

Until next time Dan Hagopian, www.batteryship.com

What You Need To Know About Lithium Ion Batteries

Used for many popular handheld devices from iPods to iPAQs lithium-ion batteries are ideal for mobile electronics. They are lightweight, energy-dense, and have a chemistry composite allowing the battery to recharge fast. But what is lithium, where does it come from, how is it made into a battery, what does it look like, and where can I get it?

Here is a quick list of the chemical characteristics of lithium

• Name: lithium
• Symbol: Li
• Atomic number: 3
• Atomic weight: [6.941 (2)] g m r
• Chemical Abstract Service Registry ID: 7439-93-2
• Group number: 1
• Group name: Alkali metal
• Period number: 2
• Block: s-block
• Standard state: solid at 298 K
• Color: silvery white/grey
• Classification: Metallic

You will not find lithium lying around in the open as lithium does not occur as the free metal. Lithium however is a component of nearly all igneous rocks and many natural brines with large deposits located in California and Nevada both in the good ole USA. You will find lithium in the rock forms spodumene, lepidolite, petalite, and amblygonite.

Lithium is extracted, one way, from the rock by heating the rock to 1100°C, mixing with sulphuric acid, H2SO4, and heating to 250°C. Then it is followed by extracting into water to create a lithium sulphate solution, Li2SO4. At this point then it can be used for various manufacturing purposes.

Lithium has high electrochemical potential and thus is used as a battery anode material in dry cells and storage batteries. In fact the energy of some lithium-based cells can be five times greater than an equivalent-sized lead-acid cell and three times greater than alkaline batteries. Lithium cells often have a starting voltage of 3.0 V. This means that batteries can be lighter in weight, have lower per-use costs, and have higher and more stable voltage profiles.

Here are some facts for lithium-ion battery cells:

• The lightest of all metals
• The greatest electrochemical potential
• The largest energy density for weight.
• The load characteristics are reasonably good in terms of discharge.
• The high cell voltage of 3.6 volts allows battery pack designs with only one cell versus three.
• It is a low maintenance battery.
• No memory and no scheduled cycling is required to prolong the battery's life.
• Lithium-ion cells cause little harm when disposed.
• It is fragile and requires a protection circuit to maintain safe operation.
• Cell temperature is monitored to prevent temperature extremes.
• Capacity deterioration is noticeable after one year (whether the battery is in use or not).

Here are some facts for Lithium Polymer Battery Cells:

• The lithium-polymer differentiates itself from the conventional battery in the type of electrolyte used (a plastic-like film that does not conduct electricity but allows ion exchange - electrically charged atoms or groups of atoms).
• The polymer electrolyte replaces the traditional porous separator, which is soaked with electrolyte.
• The dry polymer design offers simplifications with respect to fabrication, ruggedness, safety and thin-profile geometry.
• Cell thickness measures as little as one millimeter (0.039 inches).
• Can be formed and shaped in any way imagined.
• Commercial lithium-polymer batteries are hybrid cells that contain gelled electrolyte to enhane conductivity.
• Gelled electrolyte added to the lithium-ion-polymer replaces the porous separator. The gelled electrolyte is simply added to enhance ion conductivity.
• Capacity is slightly less than that of the standard lithium-ion battery.
• Lithium-ion-polymer finds its market niche in wafer-thin geometries, such as PDA batteries.
• Improved safety - more resistant to overcharge; less chance for electrolyte leakage.

Until next time, Dan Hagopian www.batteryship.com

Lithium ion Rechargeable Batteries

Lithium ion rechargeable batteries, similar to the ones seen at BatteryShip.com are by far one of the most important technologies that have been developed over the last 10 years. Lithium based batteries are used in most portable devices from PDAs to laptops to digital cameras. Lithium ion rechargeable batteries are not hazardous when sealed and used according to the recommendations of the manufacturer.

There a number of electrochemical components contained inside a lithium battery that can cause it to be dangerous. Again let me stress that when sealed and used according to the recommendations of the manufacturer lithium ion rechargeable batteries are not hazardous.

However contained inside a battery are components that convert chemical energy into electrical energy and these components if not carefully designed can become dangerous. Why? Because it is basis of the design!

The basic design of a battery includes two electrodes, an anode and a cathode.  The battery’s purpose: to create current, from which we get voltage, the power to make our devices work while on the go. But the same power can also be quite dangerous if not manufactured and or used correctly. Let’s look closer at the battery’s design.

The two electrodes contained within the battery are the anode and the cathode. The anode is where oxidation occurs. During oxidation oxygen is added to the electrode which causes the removal of electrons from the specific chemical compound (e.g. lithium). The cathode is where reduction (gain of electrons) takes place. A Redox reaction is one where electrons are gained from an oxidizing source. In a battery it is in the anode where oxidation occurs to pass electrons to the cathode.

From the anode to the cathode electrons are passed through an electrolyte. An electrolyte is a scientific term for salt, specifically ions. The term electrolyte means that an ion is electrically-charged and moves to either a negative or positive electrode. The electrolyte is a substance containing free ions which behaves as an electrically conductive medium.

Electrolytes are typically formed when the force of salt is placed into a solution. The force of the salt (not to mention the salt itself) separate the atomic components of the solute molecules in a process called chemical dissociation. The solution can be any number of things such as a solution of lithium hexaflourophosphate (LiPF6) in a mixture of Organic Solvents: [Ethylene Carbonate (EC) + DiEthyl Carbonate (DMC) + DiEthyl Carbonate (DEC) + Ethyl Acetate (EA).

In batteries electrolytes are used to store energy as chemical fuel on the surface of the metal plates within battery cell and the electrolyte also serves as a conductor, which connects the plates electrically.

In some of the lithium batteries at BatteryShip.com for example the electrolyte is a gel-like polymer film that allows ion exchange. The dry polymer electrolyte design offers simplifications with respect to fabrication, ruggedness, safety, a razor thin-profile geometry, and enhanced conductivity. The electrolyte is held within a dry cell which is a galvanic electrochemical cell containing the pasty electrolyte.

Under normal conditions of use, the solid electrode materials and liquid electrolyte they contain are non reactive provided the battery integrity is maintained and seals remain intact. There is risk of exposure ONLY in cases of abuse (mechanical, thermal, electrical), which leads to the activation of the safety valve and/or the rupture of the battery container. Electrolyte leakage, electrode materials reaction with moisture/water or battery vent/explosion/fire may follow, depending upon the circumstances. Consequently the battery may bulge, bubble, smoke, or catch on fire in extreme circumstances. However if constructed and used according to the manufacturers recommendations lithium rechargeable batteries are perfectly safe and very useful.

Until next time - Dan Hagopian, www.batteryship.com

Battery Recall – Are Lithium Batteries Safe?

With the battery recalls that have recently occurred with both Dell and Apple many people have been writing about battery safety issues. Since BatteryShip is in the business of selling rechargeable batteries we would like to say emphatically that lithium ion batteries are perfectly safe. In fact with the lithium ion batteries we have been selling we have found that less than 1% of the batteries we have are ever defective. Furthermore we have never had a case where one of the batteries we have sold has caught fire. In addition to that in my last 10 years in the industry and having sold millions of these battery technologies I can say that without question these batteries are safe.

Personally I believe that many of the recalled batteries more than likely did not even need to be returned. But I do understand from a precautionary stand it is far less costly to recall a battery then go through any legal proceedings that may arise from a defective battery that explodes.

During the latest round of recalls media outlets have been making statements that lithium ion battery packs contain cells of rolled up metal strips. This is true. They continue to report that during the manufacturing process at a Sony factory in Japan, crimping the rolls [of electrolytes] left tiny shards of metal loose in the cells, and some of those shards caused batteries to short-circuit and overheat, according to Sony. This may be true. If it is true then the cause is not in lithium technology but a mistake made during the manufacturing process of the batteries at Sony’s plant.

Regardless of the mistakes made in Sony’s manufacturing process a small percentage of batteries can and do fail. Battery failures occur for a number of reasons including:

• Batteries can have faulty cell design
• Batteries can be manufactured under uncontrolled processes
• Batteries can be operated in uncontrolled conditions
• Batteries can be abused
• Batteries can degrade and lose power (this is actually not a defect but the natural lifecycle of a battery during normal usage)

Battery Cell Design Faults – include weak mechanical design, inadequate pressure seals and vents, the specification of poor quality materials and improperly specified tolerances can be responsible for many potential failures.

Uncontrolled Manufacturing Processes include – badly run production facilities which lead to cell short circuits, leaks, unreliable connections, sealing quality, mechanical weakness, and contamination. An example of a manufacturing process out of control is variable coating thicknesses of the active chemicals on the electrodes would affect cell capacity, impedance and self discharge.

Uncontrolled Operating Conditions - perfectly good batteries fail when you use operate them in conditions where they shouldn’t be like: using the battery in a device that it was not specifically designed for, charging the battery with an incorrect adapter/charger, extreme environmental conditions (most handheld consumer batteries operate best when ambient temperatures are between 32°F-95°F), and physical damage.

Abuse - Abuse means deliberate physical abuse by the end user as well as accidental abuse which may be unavoidable. This may include dropping, crushing, penetrating, impacts, immersion in fluids, freezing or contact with fire.

Battery Degradation and Power Loss - A battery over time degrades and eventually stops working, this is no surprise, but why this occurs is really a fascinating yet technical process. These reasons are complex issues that are way beyond user control and are wholly contained within your battery and within your device! These reasons for battery degradation and power loss over time is due to declining capacity, increasing internal resistance, elevated self-discharge, and premature voltage cut-off on discharge.

Until next time Dan Hagopian, BatteryShip.com

How Do Batteries Work?

A battery is a device that converts chemical energy into electrical energy. The basic design of a battery includes two electrodes, an anode (the positive end) and a cathode (the negative end). In between the battery’s two electrodes runs an electrical current caused primarily from a voltage differential between the anode and cathode. The voltage runs through a chemical called an electrolyte (which can be either liquid or solid). This battery consisting of two electrodes is called a voltaic cell.

The first inclination that an electrical path-way from an anode to a cathode within a battery or in this first instance “a frog” occurred in 1786, when Count Luigi Galvani (an Italian anatomist, 1737-1798) found that when the muscles of a dead frog were touched by two pieces of different metals, the muscle tissue twitched.

This led to idea by Count Alessandro Giuseppe Antonio Anastasio Volta (Feb. 18, 1745- March 5, 1827), an Italian physicist who realized that the twitching was caused by an electrical current that was created by chemicals. Volta’s discovery led to the invention of the chemical battery (also called the voltaic pile) in 1800. His first voltaic piles were made from zinc and silver plates (separated by a cloth) put in a salt water bath. Volta improved the pile, using zinc and copper in a weak sulfuric acid bath and thus invented the first generator of continuous electrical current.

The batteries we use today are simply variations of the early battery or voltaic pile. Today’s battery’s are made up of plates of reactive chemicals separated by barriers, being polarized so all the electrons gather on one side. The side that all the electrons gather on becomes negatively charged, and the other side becomes positively charged. Connecting a device creates a current and the electrons flow through the device to the positive side. At the same time, an electrochemical reaction takes place inside the batteries to replenish the electrons. The effect is a chemical process that creates electrical energy (electrochemical energy).

Now with this backdrop let’s look more closely at one popular battery – the iPAQ Battery 167648 and use this battery as an example of what type of electrochemical reaction is occurring inside your battery to create power. Most batteries function in a similar fashion so this example should provide a basic back drop.

As you look at the iPAQ Battery 167648 at BatteryShip.com you will see that the technical specs are:

• Polymer Lithium
• 3.7 volts
• 1600 mAh
• 100% OEM compatible. IPAQ 167648 Battery is guaranteed to meet or exceed OEM specifications.
• Integrated Power Management Circuits - protect against over-voltage and under-voltage conditions and maximizes battery life between charges, minimizes charging times, and improves overall battery life.

These specifications are actually the measurements of some of the technical operations that are taking place inside the iPAQ 167648 Battery while the battery is powered and they quantify the energy that is used to power your iPAQ 167648 Battery.

The iPAQ 167648 Battery is the power source for the iPAQ 167648 PDA. The iPAQ 167648 battery converts chemical energy into electrical energy and that conversion is the basis of the energy formed to power the iPAQ 167648 Battery and device.

Inside the durable casing of the iPAQ 167648 Battery is an internal system design that includes two electrodes, an electrolyte, plates of reactive chemicals, and a dry cell.

Working in concert with each other each of these parts perform a specific function: to create electrical current to power the IPAQ 167648 Battery and device.

Let’s look closely at the internal design of the iPAQ 167648 battery.

The two electrodes contained within the iPAQ 167648 battery are the anode and the cathode. The anode is the positive electrode and it is where oxidation occurs. During oxidation oxygen is added to the electrode which causes the removal of electrons from the specific chemical compound (e.g. lithium). The cathode is where reduction (gain of electrons) takes place. A Redox reaction is one where electrons are gained from an oxidizing source. In the iPAQ 167648 Battery it is in the anode that oxidation occurs to pass electrons to the cathode.

The passing of electrons from the anode to the cathode is passed through an electrolyte. The electrolyte is a gel-like polymer film that does not conduct electricity but allows ion exchange. The dry polymer electrolyte design offers simplifications with respect to fabrication, ruggedness, safety, a razor thin-profile geometry, and enhanced conductivity. The electrolyte is held within a dry cell which is a galvanic electrochemical cell containing the pasty electrolyte.

As electrons pass through the electrolyte we can measure their volume in amperes (Amps) at a rate of one Amp to every 62,000,000,000,000,000,000 electrons per second.

[One side bar: In the case of iPAQ 167648 Battery the Amp rating is rated as mAh. A milliAmp hour (mAh) is most commonly used notation system for the iPAQ 167648 Battery. Note that 1000 mAh is the same as 1 Ah. (Just as 1000mm equals 1 meter.) Note that Amp hours do not dictate the flow of electrons at any given moment, that is the role of volts. An iPAQ 167648 Battery with a 1 Amp hour rating could deliver ½ Amp of current for 2 hours, or they could provide 2 Amps of current for ½ hour.]

As mentioned above as electrons are passing through the electrolyte of the 167648 Battery an electron flow is created. As the electrons flow from the anode to the cathode through the electrolyte the electron flow becomes the current created by your iPAQ 167648 Battery to power your iPAQ 167648 Battery.

Current can be measured in volts, which is the electrical measure of energy potential. You can think of it as the pressure being exerted by all the electrons of your iPAQ 167648 Battery on the cathode as they move from the anode. This “pressure” of electrons are controlled so that just the right amount of current can be sent through your iPAQ 167648 Battery battery.

So as we started with our example of the iPAQ 167648 Battery we see that when the battery is powering your iPAQ 167648 Battery there is quite a lot of controlled work that is taking place, more than we typically realize is going on.

By the way the iPAQ Battery 167648 fits the following models:

IPAQ 3135 IPAQ H3135 IPAQ 3150 IPAQ H3150 IPAQ 3630 IPAQ H3630 IPAQ 3635 IPAQ H3635 IPAQ 3650 IPAQ H3650 IPAQ 3660 IPAQ H3660 IPAQ 3670 IPAQ H3670 IPAQ 3760 IPAQ H3760 IPAQ 3765 IPAQ H3765

Until next time Dan Hagopian, BatteryShip.com

Temperature Affects Batteries?

Batteries are affected by temperature and or humidity. If batteries are too hot or too cold, then yes batteries will exhibit behaviors that would be incongruent with their normal and designed operating specifications. This is not a manufacturer defect but a direct consequence of using a battery in an environment that the battery was never designed to be used. Let us refer to this type of environment as a weather extreme.

If a battery is exposed to a weather extreme it may stop working, bulge, bubble, melt, damage your device, smoke, create sparks, create flames, expand, contract, and or even blow-up in very extreme cases.

Weather extremes, where the ambient temperature and the relative humidity of a specific environment are altered beyond the norm may occur almost anywhere and at anytime. Here are a few such examples (this is by no means exhaustive): a weather extreme can occur outside, in a non-temperature controlled room, in a closed bathroom with the shower on, in a closed car on a hot day, in a steam-room or a sauna to name a few places. Altitude also affects batteries, for example above 15,000 feet in non-pressurized cabin. Extreme cold also affects the battery as the internal components expand as direct result to A weather extreme can also occur even when the temperature is well within the range of the devices specification but the relative humidity increases the ambient temperature beyond the norm.

If a device including the battery is exposed to weather extremes for any length of time then there will be an affect; mostly a negative effect on your device and battery.

Why does temperature affect a battery - because batteries are a device that converts chemical energy into electrical energy? A battery is an electro-chemical device. A battery has two electrodes, an anode (the positive end) and a cathode (the negative end). In between the battery’s two electrodes runs an electrical current caused primarily from a voltage differential between the anode and cathode. The voltage runs through a chemical called an electrolyte (which can be either liquid or solid). This battery consisting of two electrodes is called a voltaic cell.

The batteries we use today are simple variations of the early battery or voltaic cell. Today’s battery’s are made up of plates of reactive chemicals separated by barriers, being polarized so all the electrons gather on one side. The side that all the electrons gather on becomes negatively charged, and the other side becomes positively charged. Connecting a device creates a current and the electrons flow through the device to the positive side. At the same time, an electrochemical reaction takes place inside the batteries to replenish the electrons. The effect is a chemical process that creates electrical energy.

When ambient temperature changes occur the electrons within the battery is affected. When an increase in temperature occurs the electrons are excited. A decrease in temperature inhibits electrons. This is a natural reaction on electrons in most systems. Furthermore, the combination of a rapid temperature change and high humidity can cause condensation to form and a potential hazard for your battery and device for that matter.

Until next time - Dan Hagopian, www.BatteryShip.com

What Causes Batteries to Fail?

Why do batteries fail? Can there be such a thing as a bad battery? How do I know if my battery is bad? The most effective means of understanding the status of a battery is to test the battery using a battery analyzer. However as this may not be readily available for you let’s examine some of the possibilities that could cause a battery to “fail” and also understand some things you can do to help isolate if a battery is indeed bad.

First of all batteries with different cell chemistries or constructions may fail in different ways. For example:

• Batteries can have faulty cell design
• Batteries can be manufactured under uncontrolled processes
• Batteries can be operated in uncontrolled conditions
• Batteries can be abused
• Batteries can degrade and lose power

Battery Cell Design Faults – include weak mechanical design, inadequate pressure seals and vents, the specification of poor quality materials and improperly specified tolerances can be responsible for many potential failures.

Uncontrolled Manufacturing Processes include – badly run production facilities which lead to cell short circuits, leaks, unreliable connections, sealing quality, mechanical weakness, and contamination. An example of a manufacturing process out of control is variable coating thicknesses of the active chemicals on the electrodes would affect cell capacity, impedance and self discharge.

Uncontrolled Operating Conditions - perfectly good batteries fail when you use operate them in conditions where they shouldn’t be like: using the battery in a device that it was not specifically designed for, charging the battery with an incorrect adapter/charger, extreme environmental conditions (most handheld consumer batteries operate best when ambient temperatures are between 32°F-95°F), and physical damage.

Abuse - Abuse means deliberate physical abuse by the end user as well as accidental abuse which may be unavoidable. This may include dropping, crushing, penetrating, impacts, immersion in fluids, freezing or contact with fire.

Battery Degradation and Power Loss - A battery over time degrades and eventually stops working, this is no surprise, but why this occurs is really a fascinating yet technical process. These reasons are complex issues that are way beyond user control and are wholly contained within your battery and within your device! These reasons for battery degradation and power loss over time is due to declining capacity, increasing internal resistance, elevated self-discharge, and premature voltage cut-off on discharge. For a more detailed analysis of battery degradation and power loss please visits this special report on Battery Degradation and Power Loss.

Until next time Dan Hagopian, BatteryShip.com

Battery Chemistry Types

Their exists today, for commercial consumption, 6 battery types. Their is considerable amount of work and investment dollars being poured into new fuel cell technology but as of today nothing is yet on the market. So of the battery types that are readily available they are as follows.

1. Nickel-cadmium batteries were first invented in 1899 and are a mature energy type with moderate energy density. Nickel-cadmium is used in batteries where long life, high discharge rate and extended temperature range is important. The main applications for nickel-cadium batteries are for two-way radios, biomedical equipment and power tools.

2. Nickel-metal-hydride batteries has a higher energy density compared to nickel-cadmium but at the expense of severely reduced cycle life. Applications include mobile phones and laptop computers not much needs to be talked about here since nickel-metal hydride batteries are not too commonly used anymore for your portable consumer.

3. Lead-acid batteries are the most economical portable power source for larger power applications where weight is of little concern. Lead-acid is the preferred choice for hospital equipment, wheelchairs, emergency lighting and UPS systems. The most common place where most of us find lead-acid batteries are in our personal vehicles. Automobiles, light trucks and vans almost always use a 12-volt, six cell, and negative grounded, lead acid automotive battery used to start gasoline or diesel engines. You will find lead-acid batteries in motorcycles, boats, snowmobiles, jet skis, farm tractors, lawn and garden tractors, SUVs, etc.

4. Lithium-ion batteries are widely used today since they offer significant benefits for portable consumers. Lithium is the lightest of all metals, it has the greatest electrochemical potential, and the largest energy density for its weight.The load characteristics of lithium are reasonably good in terms of discharge.The high cell voltage of 3.6 volts allows battery pack designs with only one cell versus three (less costly and compact). Lithium ion is a low maintenance battery with no memory and no scheduled cycling being required to prolong the battery's life. And finally Lithium-ion cells cause little harm when disposed.

5. Lithium-ion-polymer batteries are very similar to lithium-ion, but with an even far more slimmer geometry and simple packaging but of course with a higher cost per watt/hours. Main applications are cell phones and PDAs. The lithium-polymer differentiates itself from the conventional battery in the type of electrolyte used (a plastic-like film that does not conduct electricity but allows ion exchange - electrically charged atoms or groups of atoms). The polymer electrolyte replaces the traditional porous separator, which is soaked with electrolyte. The dry polymer design offers simplifications with respect to fabrication, ruggedness, safety and thin-profile geometry. Cell thickness measures as little as one millimeter (0.039 inches). Lithium polymer can be formed and shaped in any way imagined. Commercial lithium-polymer batteries are hybrid cells that contain gelled electrolyte to enhance conductivity. Gelled electrolyte added to the lithium-ion-polymer replaces the porous separator. The gelled electrolyte is simply added to enhance ion conductivity.
Capacity is slightly less than that of the standard lithium-ion battery. Lithium-ion-polymer finds its market niche in wafer-thin geometries, such as PDA batteries. Lithium ion also offers improved safety - more resistant to overcharge; less chance for electrolyte leakage.

6. Reusable Alkaline - Its limited cycle life and low load current is compensated by long shelf life, making this battery ideal for portable entertainment devices and flashlights. Great batteries if you want to store on demand power for a emergencies.

Until next time - Dan Hagopian, BatteryShip.com

Battery Chemistry

Since the year 1800 when the first voltaic battery was invented portable battery power has been a fascination by many. In 1991 Sony commercialized the first lithium-ion battery and in 1999 lithium-polymer came out commercially with PDAs.

But what are the differences of the two chemistries and in terms of your PDA battery which one is better? In a nutshell the two chemistry types are similar but one benefit that lithium-polymer offers is that enables slim geometry that allows it to fit in small places like a PDA.

Let's look inside the battery technology a bit more!

Lithium-ion Battery:

    * The lightest of all metals
    * The greatest electrochemical potential
    * The largest energy density for weight.
    * The load characteristics are reasonably good in terms of discharge.
    * The high cell voltage of 3.6 volts allows battery pack designs with only one cell versus three.
    * It is is a low maintenance battery.
    * No memory and no scheduled cycling is required to prolong the battery's life.
    * Lithium-ion cells cause little harm when disposed.
    * It is fragile and requires a protection circuit to maintain safe operation.
    * Cell temperature is monitored to prevent temperature extremes.
    * Ccapacity deterioration is noticeable after one year (whether the battery is in use or not).

Lithium Polymer Battery:

    * The lithium-polymer differentiates itself from the conventional battery in the type of electrolyte used (a plastic-like film that does not conduct electricity but allows ion exchange - electrically charged atoms or groups of atoms).
    * The polymer electrolyte replaces the traditional porous separator, which is soaked with electrolyte.
    * The dry polymer design offers simplifications with respect to fabrication, ruggedness, safety and thin-profile geometry.
    * Cell thickness measures as little as one millimeter (0.039 inches).
    * Can be formed and shaped in any way imagined.
    * Commercial lithium-polymer batteries are hybrid cells that contain gelled electrolyte to enhane conductivity.
    * Gelled electrolyte added to the lithium-ion-polymer replaces the porous separator. The gelled electrolyte is simply added to enhance ion conductivity.
    * Capacity is slightly less than that of the standard lithium-ion battery.
    * Lithium-ion-polymer finds its market niche in wafer-thin geometries, such as PDA batteries.
    * Improved safety - more resistant to overcharge; less chance for electrolyte leakage.

Until next time - Dan Hagopian, BatteryShip.com