KNOWLEDGE IS POWER
PART 1 OF AMERICAN SURVIVAL GUIDE’S EXCLUSIVE TWO-PART GUIDE TO BATTERIES
Part 1 of American Survival Guide's exclusive two-part battery guide
In the preparedness community, we strive to avoid, or at least minimize, our reliance on things we can’t control. Much of our gear requires only the mind, eye and hand of the operator to use and maintain—as it should be. But some of our gear depends on something often in short supply when an emergency arises: electricity.
Mission-critical equipment, such as flashlights, illuminated or holographic weapon sights, night vision devices and communications gear, requires electricity in the form of batteries. Compounding matters: There is no one-size-fits-all solution, so it’s likely that each device requires a different kind of batter than the others, making interchangeability impossible. To make use of these gadgets, we are forced to stockpile several different kinds of batteries and hope we have enough of each in reserve to make it through a prolonged crisi
Almost every home has a drawer full of batteries, neatly arranged by size and organized with the oldest ones in the front ranks, ready for use, while the freshest wait their turn at th back. (Okay; maybe that’s pushing it a bit.)
More often than not, batteries are haphaz ardly tossed in the drawer and allowed to spill out of their packaging, resulting in new batteries being dispersed among old, partially depleted cells. When the time comes for someone to replace the nearly dead batteries in the flashlight needed to conten with yet another power outage, they find themselves sorting through mixed batteries of different capacities or different chemistrie from multiple manufacturers.
The life of even the best battery could be severely shortened as it fights against the internal resistance of a nearly exhausted or incompatible companion. These marvelous, little power plants are frequently misunderstood and often abused; and, when neglected they can bleed out and die inside our electron device, rendering it ... useless.
In this article (part one of two), we will shed some light on the basics of batteries and arm you with information that will make managing that overflowing battery drawer easier—and possibly save you some money in the process.
HOW DO BATTERIES WORK?
In the simplest terms, a battery produces electrical energy as a product of electrochem ical reactions that take place inside it at the positive and negative electrodes through a
onductive chemical solution called an “elecrolyte.” When a circuit is attached to the exteor terminals, the metallic electrodes undergo redox (reduction-oxidation) reaction in which ne electrode is reduced (gains an electron); imultaneously, the other is oxidized (gives up n electron) to and through the electrolyte in he form of ions.
The metals (or metallic compounds) that orm the electrodes determine the specific oltage of the cell.
For example, if one electrode is zinc and he other is manganese dioxide, the meaured terminal voltage of a fully charged ell is a bit over 1.5 volts (open circuit oltage). This zinc-manganese dioxide lectrode combination is commonly found n the disposable batteries we use to power any of our portable devices.
In another example, if one electrode is nickel nd the other is cadmium (or other metal lloy), the cell voltage would be about 1.2 olts (open circuit). These combinations are nown as nickel-cadmium (Nicd or Nicad) or Nickel-metal Hydride (NIMH) cells. They are rechargeable batteries that can be substituted for non-rechargeable batteries of the same size and form (such as the Aa—or “double A”—batteries so common in small electronic devices). If more energy (higher voltage) is required, multiple cell are used together in series; their individual voltages add together to give a greater difference in electrical potential from one end of the chain to the other.
While there are several electrode and electrolyte combinations, as well as many different battery sizes, shapes and voltage ratings, all batteries fall into one of two types: primary or secondary.
PRIMARY (NON-RECHARGEABLE) BATTERIES
Primary batteries are single-use and are not rechargeable power sources. Immediately upon their construction, they are capable of full power output at their specified voltage. As the batter is used, the electrode materials and electrolyte undergo chemical changes that are not easily reversed by application of an external current, meaning they cannot be recharged for reuse.
Single-use batteries can last a long time, provided they are used in devices for which they are intended and are stored properly. Many small electronic devices have minimal current requirements, and the battery seems to last forever. For instance, wrist watches, television remote controls and garage door openers can operate for years on a single or a set of small, inexpensive batteries. Those same batteries might only last for a few hours in a high-output flashlight. Choosing a battery with a different chemistry can more than double or triple the run time of the device before changing batteries is necessary.
SECONDARY (RECHARGEABLE) BATTERIES
Secondary batteries are rechargeable and can be reused many times over. The manufacturing process is complex, and the materials are costlier, compared to those in most primary batteries. However, because they can be reused, they are usually much more economical than a comparable primary battery. Secondary batteries often require charging before being placed in use or after (and sometimes, during) an extended time in storage.
Rechargeable batteries can have vastly different lifespans or number of charge/discharge cycle based on the chemistry and intended use of the battery; the environment during use and storag and the charge/discharge conditions.
For example, a lead-acid starting battery in an automobile is designed to provide a brief high current to start the engine and then be quickly recharged by the alternator as the engine runs. Although the battery is capable of this high output for brief periods, leaving the headlights on can drain the battery in a relatively short time. Short-distance driving, when the engine is shut
ff and restarted frequently, can often prevent the battery from being fully charged. In both stances (deep discharge or incomplete recharging), the lifespan of the battery could be drastially shortened. A common trait in many rechargeable batteries is self-discharge. Some can lose considerable amount of power in storage; and, if they are allowed to go low enough, they might ot take a charge again.
Batteries "like" operating temperatures in about the same range as we humans do, with emperatures in the 70s (F) being the sweet spot. Just as we sleep better when the room is a bit ooler, most batteries store best at lower temperatures; somewhere in the mid-40s (F).
Both types of batteries perform best during use and store longest in a cool, dry environment. xcessive heat can shorten the life of the battery due to accelerated chemical reactions inside.
MUCH OF OUR GEAR REQUIRES ONLY THE MIND, EYE AND HAND OF THE OPERATOR TO USE AND MAINTAIN—AS IT SHOULD BE. BUT SOME OF OUR GEAR DEPENDS ON SOMETHING OFTEN IN SHORT SUPPLY WHEN AN EMERGENCY ARISES: ELECTRICITY.
Temperatures too low cause the battery to be sluggish when power is demanded, and output will drop accordingly (but the battery will return to normal once it warms up). Extreme cold can cause the electrolyte to freeze, which can cause internal cell damage or rupture of the battery housing or case.
The freezing point of the electrolyte is dependent upon a couple of factors, but fully charged batteries can withstand much colder temperatures than those that are partially or fully discharged. For instance, a deep-cycle lead-acid battery, such as those used in recreational vehicles and boats, can
ithstand temperatures as low as -90 degrees F) without fear of the sulfuric acid electrolyte eezing if the battery is at a 100 percent state f charge (SOC). That same battery with 40 ercent SOC is safe to about -16 degrees (F), ut at 20 percent SOC, it is subject to freezing t +19 degrees (F). During the winter months, is very important to keep lead-acid batteries hat are in storage fully charged to reduce the sk of freeze damage.
Storage of dry-cell batteries is best done
their original packaging. This will ensure heir terminals will not come in contact with ne another and that when taking them out f storage to use, all batteries will be at the ame charge level. Keep them cool and dry o achieve the longest life. Storing them at oom temperature is fine, but many people refer to keep them inside their refrigeraors. They also keep the batteries in their ackaging while they warm up to reduce the kelihood of causing condensation issues side the device they are to be placed. Do ot store them in the freezer!
Larger batteries, such as automotive or eep-cycle RV batteries, should be stored in cool environment, taking care to protect he terminals or posts against contact with onductive materials. Covering with a piece of lastic sheeting or a cardboard box is usually ufficient to protect the battery, but make ure not to set any heavy objects on top of he stored battery.
There used to be a concern about storing n automotive or RV battery directly on a oncrete floor, but improvements in battery onstruction and case materials have reduced he possibility of the cells discharging through he bottom of the battery. That said, I still lace any stored battery on a piece of plywood
Always keep in mind that batteries, even at a low state of charge, can be hazardous if anything conductive short-circuits their terminals. Large, lead-acid batteries can turn a crescent wrench red-hot in a matter of seconds if it falls across the positive and negative terminals. The wrench can even become welded to the terminals immediately as sparks fly upon contact, making it dif ficult or impossible to remove. Even small batteries can provide surprises (a good friend swappe out a lithium battery and put the weak cell in his pants pocket. The battery terminals became shorted by loose change in his pocket, and he received a rather nasty burn from the incident!).
OTHER BATTERY DANGERS
Batteries contain caustic or corrosive substances that can pose health risks or damage materials they come in contact with if they leak out of the cell. Batteries can rupture and leak for several reasons, including mixing batteries of different chemistry or capacity in the same device, attempting to charge a non-rechargeable battery, improper storage, disposal, overheating or freezing.
A list of warnings is printed on the battery or its packaging. Heed these warnings, and your battery should safely live up to its specifications.
In the second installment of our two-part battery guide, we will take a deeper look at batteries commonly used in our everyday gear and some of our more-specialized devices ... and we’ll put that “bunny” up against the copper in a real-world test to see which one actually lasts the longest.
Keeping batteries in their original packaging ensures new batteries don’t get mixed with used, partially discharged cells. h Below: For the sake of simplicity and efficiency, keep your batteries in their original packaging in one location so they're easy to find and move when the need arises.
A 9-volt battery gets its power from six AAAA cells contained within.
All these Aa-size batteries will fit into the same device, but mixing different battery chemisies or cell capacities can result in early battery death.
i Right: Lithium teries are made for evices demanding high current.
i Below: There are four 1.5-volt cells onnected in series inside this 6-volt ntern battery. From left to right, this oup of AA batteries includes a “general purpose” (zinc-caron), a “super heavy uty” (zinc-chloride) the longer-lasting, her-output alkaline version.
This zinc-carbon dry cell consists of a zinc outer shell, powdered manganese dioxide and an inert carbon rod. There is just enough ammonium chloride electrolyte to moisten the insid of the cell.
i Right: Exposed battery terminals can pose a hazard when using conductive metal tools nearby. In storage, cover the top of the battery to protect it against objects that might come in contact with the terminals. or thick plastic—more out of habit than anything else.h Far left: Automoti starting and Rv/marine deep-cycle batt ies last longest whe they are fully charg Storing lead-acid batteries for extend periods of time in a partially charged st can shorten their lif span considerably.i Near left: Potassium carbonate, formed by the hydroxide solution leaking from an alk line battery (Photo by Túrelio, Wikime dia Commons)