Batteries. Unless you are living some agrarian “Little House on the Prairie” lifestyle, these indispensable little marvels are utterly essential for modern life. Batteries large and small make many of our technological innovations possible and serve all kinds of purposes, from the trivial and entertaining to the critically important.
From pumping out tunes to running lifesaving medical equipment, you can’t go more than a few feet without bumping into something that relies on batteries.
Even more than everyday life, when the balloon goes up, and the situation turns truly dire, you’ll rely on batteries more than ever to power essential survival equipment and tools.
Flashlights, headlamps, lanterns, GPS systems, smartphones and more all rely on batteries. The trick is, batteries require a significant industrial base to produce, much less recharge reliably, and you’ll be able to count on neither of those things in a long-term SHTF situation.
The time has come for every prepper to bump up their battery game. You need to know what’s what when it comes to types, sizes and capabilities, how to store them and how to get the most out of them, how to recharge them and how to repurpose them.
Today we present you with the ultimate preppers guide to batteries…
Battery Know-How is Essential
Chances are you have plenty of items in your survival repertoire that rely on batteries, items you would rather not part with. Flashlights are probably the most common EDC tool that is valuable in normal as well as “exciting” times.
Weapon lights for hand- and long guns are another important link in your capabilities for self-defense. Beyond those, pretty much every modern form of communication is dependent upon electricity and all such devices that are mobile- not tied to a grid- will rely on batteries.
Do you like your smartphone? Do you like all of the wondrous abilities it affords you? That device is only made possible in such a portable footprint thanks to modern lithium battery technology.
How about those tiny, lightweight, and supremely capable handheld radios that are all the rage? Useless without batteries, and not nearly as useful if you are using crappy or improper batteries.
Unless you are one of the increasingly anachronistic preppers who refuses on principle to rely on anything that depends upon electricity to function or you plan on omitting such devices entirely from your survival plan because of some perceived weakness or flaw in your defenses that it will generate, you need to brush up on your battery knowledge.
You can screw yourself, wasting both time and money, through nothing more than ignorance.
- Do you know what batteries last the longest in storage?
- Do you know what the self-discharge rate is on your battery?
- Do you know the difference between the various types of rechargeable batteries available to consumers these days?
- Just how good are rechargeable batteries and do non-rechargeables still have the advantage for high drain devices?
These and many other questions all have answers, and if you cannot answer them accurately it is time to go to school: Battery School.
By investing just a little bit of effort in buffing up your knowledge you’ll be able to buy batteries that you can place into storage and forget about for more than a decade knowing that they will work perfectly when called upon.
You’ll know how to get the most mileage for your dollar out of any given battery that you buy and which batteries you should avoid for specific purposes.
That’s enough preamble, let’s get on with it!
Battery Anatomy and Terminology
Before you can know what you are talking about, you must know what you are talking about. Though an intricate understanding of batteries is not required to use them, the more you know the better informed you’ll be when it comes to making good choices concerning employment, storage and more.
Below are some common battery terms that you should familiarize yourself with.
*Note on terminology: Before continuing, I would be remiss if I did not address some common sources of confusion regarding battery technology and terminology. In older textbooks and reports on batteries (that still remain useful today) you might run into some terminology that does not quite sync up with what I have listed here.
For instance, the electrodes on a battery might be referred to as “plates” instead. Additionally depending on how formal or informal instructions and other reference texts are written the anode and cathode could be referred to as “contacts” or something similar.
What we refer to today as a battery- a single, self-contained source of electric power that relies on an electrochemical reaction to furnish said power- is actually more appropriately called a cell, and in eras past multiple cells connected together was referred to as a “battery”, named for such an assemblage’s resemblance to a battery of cannon.
A module consists of several cells connected either in a series or in parallel. Used to meet power requirements where using a single cell of any size would be unwieldy or inefficient.
As in “battery pack”. A battery pack consists of several modules, and is used to meet power requirements when a single module would be insufficient in the same way that a module is used to meet demands or a single cell would be insufficient.
As in “battery bank”. A battery bank is distinguished from a battery pack in that it is typically a large, practically immobile installation.
Battery banks may be small-ish, like a whole-house backup battery system, or it could be an emergency standby installation the size of an entire room, of the kind used to provide emergency standby power for communications relays and computer server networks.
The electrolyte in a battery is the chemical or combination of chemicals that contains potential electrical energy. Electrolytes may be depleted of their electrical energy in use, or they might change form in use to provide electrical power.
Some electrolytes, once exhausted, are useless and the battery must be disposed of. Others may be recharged and used again and again. Can take the form of a liquid, paste or solid.
The terminal of the battery that develops a positive charge is called the cathode. In common cylindrical batteries this terminal may be flat, or feature a small raised area known as a button, or button top.
Similarly, the terminal of the battery that develops a negative charge is called the anode. Usually flat in typical cylindrical batteries, but certain manufacturers install tiny, raised protrusions to improve connectivity when arranged with other batteries utilizing flat terminals.
Classification of Batteries
There are all kinds of batteries out there in the world. So many they are virtually countless, or at least practically countless within the confines of this article.
Among the two main types of battery, primary and secondary, there are dozens and dozens of sizes, types, configurations and other pertinent characteristics.
Further complicating matters, standardization varies somewhat depending on where you live in the world and what technical agency is describing the battery in question.
The International Electrotechnical Commission and American National Standards Institute have differing opinions on the matter, as do the countless national agencies and bodies assembled for the same purpose.
To keep this article from turning into a door-stopping encyclopedia, I will be sharing with you the most common standardized types typically encountered in the United States and North America.
***Caution: Physical interchangeability or identical size is not the sole factor in determining suitability of a battery for use in a specific device or for a specific purpose. Batteries that are physically identical may have wildly varying characteristics regarding voltage, output and more. It is up to you to be certain of the suitability and safety for using any given battery in any device or for any purpose.***
Batteries are divided into two broad types:
Primary cells are capable of producing current immediately upon assembly. Most notably, primary cells are used until they’re electrical power is exhausted and then they are disposed of. The chemical reactions that supply power are not as a rule reversible and so these batteries cannot be recharged.
Colloquially, these are known as non-rechargeable batteries or cells. Primary batteries are most commonly employed for portable devices that do not experience constant use and are low drain, or in any device that is located in such a way that alternative power sources are not practical or too expensive.
As a general rule, primary batteries have higher energy densities than secondary batteries. Alkaline batteries are among the most common disposable primary batteries commercially available.
Secondary batteries are capable of being recharged by applying electric current directly to the battery itself, regenerating the reactants in the electrolytes so that they may be used to supply electricity again.
Most secondary batteries rely upon a specific charging device to accomplish this safely and reliably. Secondary batteries may be encountered in small scale or large-scale formats, and among the most common of the type are lead acid batteries, typically used to supply power to vehicles.
Certain formats of secondary battery experience high rates of self-discharge, though newer chemical formulations provide both excellent power density, peak output and very low self-discharge rates.
Common Primary Batteries
Below are common electrolyte formulations employed in primary batteries. Of the three major “branches”, lithium, nickel and alkaline, each specific formulation has its own set of advantages and disadvantages, and will typically be encountered in batteries intended for a specific purpose in order to optimize return on investment.
- Lithium: Expensive and highly energetic, lithium batteries are one of the most commonly available today for high drain or power-hungry devices of all kinds.
- Li. Iron Disulfide: A pricey lithium battery electrolyte formulation that is commonly employed in any batteries where extra power is required in a given format.
- Li. Copper Oxide: An obsolete lithium electrolyte formulation that is nonetheless still encountered when breaking old batteries out of mothballs. Has been completely replaced by silver oxide equivalents.
- Li. Manganese Dioxide: Another expensive lithium formulation that is typically only used when an extremely long shelf life is desired or for particular use in very high drain devices. Noted for an extremely low rate of self-discharge. Batteries that are typically marketed as lithium usually refer to this electrolyte formulation.
- Nickel: Most nickel electrolyte formulations produce moderate energy density for modest price, making them a reasonable choice for most applications though they see much more use today in secondary cells.
- Nickel-oxyhydroxide: Typical primary cell electrolyte formulation utilizing nickel. Good energy density and reasonable cost while still being good for most high drain applications
- Alkaline: the most common type of modern battery, these account for more than 80% of all batteries made in the U.S. Alkaline electrolyte formulations derive energy from the reaction that takes place between zinc metals and manganese dioxide. They typically enjoy a high energy density and voltage output, but struggle with typically high self-discharge rates and low shelf life compared to lithium formulations.
- Zinc-manganese dioxide: Common type of alkaline primary cell. Average energy density, suitable for both high and low drain devices.
- Zinc-chloride: This is a formulation typically employed for heavy duty applications where charge durability is an asset.
- Zinc-carbon: An older and less expensive electrolyte formulation.
Common Secondary Batteries
Just like primary batteries above, secondary batteries employ a variety of electrolyte formulations to serve various purposes. Some are common, others are rare, but all are rechargeable.
- Nickel: Nickel electrolyte compositions are among the most common in secondary batteries. Compared to other base elements, nickel formulations show the most variability depending on secondary chemicals.
- Nickel-cadmium: A common but contentious secondary cell formulation, nickel-cadmium batteries are inexpensive, have modest energy density, and are capable of withstanding rapid discharge rates without losing much in the way of capacity. They are suitable for both high and low drain applications, but also suffer from quick self-discharge rates. The environmental and health hazards posed by cadmium mean these are commonly banned outside of the United States.
- Nickel-zinc: Nickel-zinc formulations are commonly used as a one-to-one replacement for alkaline primary cells. Modest price, capable of running high drain devices and suffering from a lower rate of self-discharge than nickel-cadmium, nickel-zinc batteries have only been commonly available since 2010. Notably available in far fewer standard sizes than other batteries.
- Nickel-metal hydride: Nickel-metal hydride secondary cells perform better than traditional alkalines in devices with high energy demands and are notably inexpensive. Various tweaks to the formulation have been made over the years, and this means that older batteries may have excellent energy density but suffer from a high self-discharge rate. Newer energy densities enjoy a much lower rate of self-discharge but give up anywhere from a quarter to half of their energy density compared to the older formulation.
- Lithium: Once again lithium can get it done. It remains very energy dense and capable of excellent performance as a secondary cell in high drain devices, but it is volatile and there are significant safety hazards involved you must be aware of.
- “Lithium ion”: This is a catch-all category for various lithium electrolyte chemistries. Notably, they are very expensive but enjoy extremely high energy densities. Commonly used for smartphone, laptops, digital cameras and other power hungry portable devices. They have extremely low rates of self-discharge, and would pretty much be the perfect secondary cell if it wasn’t for their volatility. If damaged, overheated or short-circuited the cell can explode violently or easily catch fire.
- Lithium-iron-phosphate: A modified lithium ion electrolyte composition that contains neither nickel nor cobalt. Low conductivity but extremely stable, excellent safety characteristics (compared to normal lithium ion secondary cells) and excellent long-term stability. Promising applications for vehicle and backup power roles.
- Silver-zinc: Considered obsolete for a time due to the high cost of silver, silver-zinc compositions otherwise favorably compare to lithium ion electrolytes with the notable exception of a smaller overall volume. Excellent energy density and overall performance in extremely high drain applications. Notably, and worryingly, the chemical reactions of this battery are not completely understood. Suspected drops in terminal voltage believed to be caused by the creation of argentic oxides. Most recent developments in silvers-zinc formulations are seeing it once again proposed as a potential replacement for increasingly expensive lithium ion cells.
- Lead-acid: Very commonly used for automobile batteries. High lead and corrosive acid content presents health and environmental hazards and greatly increases weight. Fairly expensive, moderate energy density and self-discharge rates. Notable for significant loss of capacity when placed under high discharge load.
Common Battery Sizes and their Uses
The following list of standardized battery formats represents some of the most common primary and secondary types you can expect to see and use throughout the United States and North America. All of the following have applications in various consumer goods.
- AA: A venerable format that has been around since 1907, not officially ANSI categorized until 1947. Used in all kinds of household and consumer electronic devices. Note, lithium versions are available but are not technically AA format batteries at 3.7 volts. Certain lithium variations are interchangeable with standard AA batteries due to internal voltage regulator.
- AAA: Another old format that has been around since 1911. Commonly used in small personal electronics, decorations and small flashlights. Periodically encountered in compact radios and walkie-talkies.
- AAAA: A comparatively rare standard format, usually only seen in a pen style flashlight or inspection lights, electronic styluses, calculators, illuminated fishing lures and laser pointers.
- C: Used in older generation flashlights, work lights and radios. Essentially a high density AA, has exact same length as typical AA cell, and may be replaced as primary cell by using adapter or sabot.
- D: The original flashlight battery, first introduced in 1898. Today used for high drain devices that will benefit from enhanced capacity over smaller cell formats. May be replaced by standard AA’s using a size adapter although runtime will be drastically affected by loss of capacity.
- F: Listed here for completeness, F cells are virtually never encountered as standalone primary batteries. Such cells are typically integrated as a module and used as a common, rectangular lantern battery.
- CR123A: One of the most common lithium primary cells. Same size format also available in rechargeable lithium ion version. Typically used for maximum energy density in high drain devices such as tactical flashlights, cameras and UV water purifiers.
- E (a.k.a. 9-volt): Most commonly encountered domestically as a smoke alarm battery or radio battery. Sometimes used in high drain remote controls. Interestingly, some commercially marketed 9-volt primary batteries contain six cylindrical batteries similar to AAAA cells. Of particular interest to preppers since a field expedient fire starter can be made by combining a 9-volt battery and common steel wool.
- Lantern: Rectangular, so-called “lantern” batteries are available in a variety of formats with a variety of connections. Some feature screw-in terminals for high vibration and shock applications whereas others rely on the common (and failure) prone spring terminals. Notably certain lantern batteries are actually just modules containing multiple smaller cylindrical primary cells.
- Flat/Thin: There exists a great variety of extremely flat, thin batteries that are typically lithium ion secondary cells and used to power the most energy hungry devices such as laptops and smartphones. Many of these batteries are designed to be non-removable for the user, and are fairly notorious for creating an explosion or fire hazard when damaged.
Considering Batteries in a Survival Context
All of the above “facts for nerds” are great, but without putting it all into the context of a survival situation, specifically what you need your batteries to do for you in a survival situation, it amounts to nothing more than some winning information for a round of Trivial Pursuit.
Batteries are a consumable or semi-consumable resource during a long-term crisis and every prepper knows by now that making the best possible use of your resources is what will separate the savvy survivor from just another dead victim in the background.
Consider the following factors when choosing equipment that runs on batteries and also when purchasing the batteries themselves.
Understand that batteries can and will self-discharge!
The brand new batteries that you buy and place into storage on your shelves among all of your other gear and provisions will not last forever. Even if you leave them in the package, even if they have never been used, even if you place them on an insulating mat they will slowly, steadily lose their charge.
This is what is called self-discharge, and all batteries of all types have a different self-discharge rate. For instance, CR123A lithium batteries lose only a tiny fraction of their total power over a decade.
The same cannot be said of traditional alkaline primary cells which could give up 30% or even 50% of their charge in the same amount of time. Other batteries fare far worse.
If you purchase a type of battery that has a high self-discharge rate and is also a cut-rate option with low energy density and low capacity you could find those batteries uselessly dead and just a couple of years.
You need to understand what you require from batteries you are purchasing as a contingency prep. For powering your TV remote or your garage door opener pretty much anything will do.
If you are purchasing batteries to run essential “life support” equipment or defensive tools you need to buy batteries from good makers that have an excellent shelf life.
Don’t forget to rotate your batteries just like you’d rotate food or anything else that is perishable!
It pays, also, to keep in mind what you’ll be using your batteries for. Every device has a sweet spot when it comes to the cell powering it and it is worthwhile to figure out which battery type and brand can come closest to that spot. This will ensure the optimum combination of longevity and performance.
For instance, quite a few modern flashlights can run on multiple types of battery, but only one of them will provide it with maximum brightness, full brightness over time and long run time. Choose another type of battery and you’ll give up one or even two of those characteristics.
And not everything is about flashlights and GPSs. What if you or someone else relies on essential life support equipment like an insulin pump, hearing aid or something similar? Do you really want to take your chances with inferior cells?
No matter what you are buying batteries for always consider the likelihood that you’ll be storing them for a long time before they’ll be used: the best possible battery for constant operation might have an unacceptably high rate of self-discharge as discussed above, making it useless or suboptimal at best for your purposes.
Before you can determine how many batteries you need you need to figure out how long your batteries will function in a given device under a specific usage tempo. And when I say “your batteries” I mean Brand X or Brand Y batteries, because they are all created differently with different essential characteristics and capabilities.
How long will that 12 pack of batteries run your flashlight? The manufacturer might promise a certain number of hours of runtime at a certain setting but how do you know, really? Have you tested it? If you have tested it, what brand of battery did you use?
You might buy a couple of packs of batteries assuming that you’ll get a couple of months of use out of your flashlight but if it is an energy hog you could be sorely disappointed.
In the same example, also consider what it means to your useful run time of your battery supply if your usage tempo goes up dramatically for any reason.
Only good, meaningful, empirical data helps us make good decisions when it comes to provisioning ourselves. Make sure you have all the facts because if you don’t, you’re just guessing.
Temperature is a big influence on battery performance. Both high and low ambient temperatures can significantly degrade battery performance, potentially robbing them of both useful life and optimal output.
Combine that with the high demands of certain devices or other pieces of equipment and you might have a recipe for battery failure.
Every electrolyte formulation, from lead-acid vehicle batteries to the latest and greatest lithium ion types, all show varying levels of performance in various environments.
Make sure you carefully research the performance metrics that you can expect from your batteries in both temperature extremes of your locale. And also, make sure you test it!
Data is fine, but empirical evidence is where the rubber meets the road. It would not do to be let down by your batteries during a critical moment.
Consider the use of Battery Spacers
One useful tool that is typically unknown to most preppers is the battery spacer, sometimes called a sabot.
A battery spacer is a device that allows you to use much smaller, typically less energy dense cells of the same voltage rating and output in a device that typically utilizes larger cells.
All you need to do is insert the smaller battery into the battery spacer, and then insert the spacer cell combo into the device like you would its usual battery.
A great example of this is a battery spacer for C or D cell electric lanterns. These batteries are usually a loss leader when it comes to value because they are large, heavy, pricey and a lantern is not a tool you are likely to use all the time.
Considering most C and D format cells are non-rechargeable and alkaline in nature their comparatively short shelf lives means you’ll be shelling out tons of cash on keeping your supply rotated and in good shape.
Battery spacers could allow you to substitute regulated lithium battery equivalents for these power hungry lights in a pinch or even as a primary solution.
Even if you are not relying on battery spacers for full-time use they are a great contingency item for any savvy prepper because it allows you better flexibility to improvise solutions.
Rechargeability is Important Capability
It shouldn’t take much imagination for you to see the advantage in secondary cells, rechargeable batteries.
Primary cells represent a very poor return on investment, first because they are expensive, and second because they must be thrown away when they are expended.
This means you’ll need to shell out tons of dough feeding devices replacement batteries over time and, not for nothing, the manufacture of and waste produced by primary cells contributes greatly to pollution.
How much better would it be to simply feed your batteries a little bit of electricity to recharge them and make them useful once more?
The savings over time are enormous, and compared with eras gone by rechargeable battery technology is in many ways completely equivalent to non-rechargeable batteries and even superior in several important characteristics.
Obviously, you’ll need electricity to recharge your secondary sales and this is where most preppers tap the brakes.
You are getting all of these batteries to fuel your devices likely because you won’t be able to rely on electricity as usual in the middle of a crisis event.
What good does a rechargeable battery do if you don’t have electricity to recharge it?! As it turns out, you can probably make your own electricity, too.
Like never before, preppers now have the ability to both generate and store large amounts of electricity all on their own whether they are bugging out or bugging in.
Portable and large fixed solar arrays allow anyone to harvest the clean, plentiful and reliable radiation produced by the sun before converting it to electricity that can then be put to use immediately or stored in a separate battery pack or battery bank. Either is suitable for running a charger capable of recharging your batteries.
Another alternate option is to install a whole house battery bank, typically a large linked set of deep cycle batteries or smaller battery packs capable of providing all the electricity you need for the appliances and devices you typically run in your house.
A large reserve of batteries like that is more than capable of running a charger that will fuel your comparatively tiny secondary cells.
It might seem like more work up front but investing in correct rechargeable battery technology early in your prepping journey will save you a ton of money and even more grief over the long run.
Storage and Safety Concerns
Now that you know everything you need to know about batteries and have decided to buy a great, big bunch, the next thing you’ll need to learn is how to properly store them. Correct storage of batteries will extend their life and increase safety.
Don’t handle or store your batteries carelessly, as many modern variations, particularly lithium electrolyte formulations, are extremely energetic and can react violently if damaged or stored improperly.
Stack and Pack Them Correctly
Have you ever been over to someone’s house who has that general purpose, sort of riff-raff or junk basket in a drawer or cabinet?
You know, the one full of outlet adapters, mismatched screws and nails, a variety of cheap hex keys from IKEA furniture sets and, of course, their collection of batteries they have to dig and sort through when they need one.
That is a perfect picture of what improper battery storage looks like. When storing your batteries, you should take care to do so properly both so you do not accelerate self-discharging but also to ensure that they are not damaged while in storage, facilitating equipment malfunction or even an electrolyte leak.
The best thing you can do is keep your batteries in your factory packaging if you aren’t going to place them in a purpose-made container that is properly sized for the batteries you are storing. Though all batteries have an insulated wrapper or outer container (in the case of a battery module or pack) you should not allow either electrode to contact other batteries or any conductive surface.
You definitely shouldn’t store your batteries rolling around loose in a mixture of a bunch of other bullcrap because the likelihood that their insulation gets damaged or the casing of the battery itself ruptures increases dramatically.
Those leaking chemicals are always a health hazard and many times are caustic, to say nothing of the fire hazard that they pose.
Also, make sure you store your batteries in a room temperature place that does not get any direct sunlight.
Additional Storage and Handling Concerns for Lithium Batteries
Serious business. So what can you do to minimize the chances of your lithium battery playing arsonist or grenade? As a rule, avoid keeping any lithium battery or any device currently powered by lithium battery in a high temperature environment.
High temps will increase the strain on the battery, but also increase the chances of thermal runaway. Definitely don’t leave these batteries in your vehicle during the summer on a hot day!
Second, it is a good idea to store your lithium batteries in compartments, with spaces or breaks between them, or at least spaces between each group of batteries. This can reduce the risk of a chain reaction and the severity of a fire hazard should it occur.
Lastly, treat these batteries as exactly what they are: tiny vessels containing dangerous, highly reactive and extremely energetic chemicals. Don’t let them bang around in your backpack with a bunch of other crap, don’t let them get crushed and store them and crush proof containers.
Lithium batteries, be they primary or secondary cells, are always an asset but one you must handle with caution.
Useful Terminology for Advanced Users
If you are really serious about making the most of your batteries and learning how to “hack” them for other useful purposes besides their prescribed usage you’d be smart to start brushing up on some of the advanced terminology below.
State of Charge: Technical jargon that expresses the current capacity of the battery as a percentage compared to its maximum capacity.
Terminal Voltage: The actual voltage between the battery’s terminals once a load is applied. Terminal voltage is variable depending upon the state of charge and charging or discharging current.
Open-Circuit Voltage: Similar to terminal voltage, only this is an expression of the voltage between the terminals with no load applied. Again, dependent upon the state of charge.
Depth of Discharge: This expresses the percentage of the battery’s capacity that has been discharged, compared to its maximum capacity.
Internal Resistance: The resistance of the battery dependent upon the state of charge. This figure is often different for charging and discharging, and as internal resistance increases efficiency goes down and thermal stability is diminished.
Nominal Capacity: Total amp hours available when the battery is discharged at a particular current from 100% state of charge to cut off voltage. See ‘cut-off voltage’ below.
Nominal Voltage: This is the reported or manufacturer referenced voltage of the battery. As you might expect, can vary significantly from actual voltage depending on conditions and use.
Cut-off Voltage: The minimum allowable voltage the battery can produce. When a battery is empty it is actually more likely that it has reached the cut-off voltage.
Nominal Energy: The total energy capacity of the battery, expressed as hours available when the battery is discharged at a certain current from 100% charged until it reaches cut off of voltage.
Specific Energy: Expresses a battery’s nominal energy per unit of mass. Specific energy is characteristic of a particular battery type and electrolyte chemistry. Also called gravimetric energy density.
Cycle Lifespan: This is the number of discharge and recharge cycles that a battery can endure before it can no longer meet specified performance criteria. A specified number might vary greatly depending on the usage tempo and recharging protocols employed.
Note that extremely specific performance criteria might mean that a battery experiences a low cycle lifespan compared to a different set of criteria that is less demanding.
Should you keep your batteries in a Faraday cage?
There is a considerable amount of discourse concerning whether or not a prepper should keep their batteries in some sort of protective envelope or container in case of an EMP event, be it naturally occurring or man-made.
In case you are unfamiliar, an EMP, or electromagnetic pulse, from any source that is powerful enough will basically fry any circuit board and most electronics that are not specially protected. It seems reasonable that batteries might be damaged or discharged during such an event even if they are not connected to a device.
The physics of such an event are far beyond my education on the matter, but my research into the subject shows that the preponderance of experts seems fairly certain: So long as your batteries are not connected to a device, they should not be affected by an EMP.
All batteries have an insulating wrapper or container that holds them, but more than that, the battery by design is insulated against such an event so long as it is not installed. That means you should be able to pull your battery out of storage and pop them in a device that was not otherwise damaged by the EMP and expect them to work.
Now, it certainly wouldn’t hurt anything to store your batteries in a Faraday cage or other object that can provide protection against an EMP so long as you follow the other storage guidelines above.
Are Lithium Batteries Really Dangerous?
Yes and no. Modern lithium batteries produced by manufacturers who actually give a damn about quality control and quality assurance are very safe.
But suffice to say that not all manufacturers, particularly those in China, are so concerned with putting out a quality product and keeping the populace safe.
No matter how you square it, all lithium batteries are particularly energetic and should they malfunction or become damaged there are more than capable of creating a fire as they burst into flames or even violently exploding. Yikes.
I have witnessed such an event myself with cheap lithium batteries used in a high output weapon light mounted on a rifle, so believe me when I say that you don’t want this to happen to you.
Part of the problem is in the inherent design of most lithium batteries: These batteries are, as a rule, very lightweight and also expected to put out a dramatic amount of power over a long time.
As you can imagine, the interior design and construction of a lithium battery, from the cathode and anode to the organic solvents and lithium salts themselves are kept in a delicate, precise arrangement in order to function. The contents are also typically under pressure.
But the demand for lightweight and ever higher performance means that lithium batteries are comparatively fragile, and easy to damage.
Once a lithium battery is damaged a short is likely, and if the casing of the battery has been compromised a spark will easily ignite the super reactive lithium salts within. Then you’ve got a fire, and a bad one out of all proportion with the size of the battery.
Another unhappy occurrence that typically results from poor manufacturing processes and a lack of quality control is thermal runaway.
When this occurs the battery heats up to the point where the internal pressure of the battery starts to increase and, by one method or another, the output increases further increasing the heat until eventually- Kaboom! Once again, a lithium battery can explode with force out of all proportion to its size.
Batteries are devices that quite literally make modern life possible. Without them, our tools and technology would be far less mobile and the logistics required to bring electricity far from established power grids would become too costly in many cases.
Every prepper understands that they will have a great need for batteries in the aftermath of an SHTF situation, and just like any other skill set and any other piece of equipment it is in your best interest to learn everything you can about batteries in order to get the best possible use out of them and the best return on your investment.