Batteries

When it comes to being prepared, batteries are one of the most important items to have on hand. But it isn't as simple as just buying a bunch of batteries, throwing them in a drawer, and calling it good. There are lots of battery types and they all have different purposes. While we could get into anodes, cathodes, electrolytes, and electrochemical reactions, I've decided that this is probably outside the scope of what I really want to cover. So we'll skip all that and focus on the common types of batteries and what each is best suited for. So here you have it... Batteries 101. 

Types of Batteries:

There are basically two types of batteries: Primary and Secondary

• Primary batteries are non-rechargeable. You use them one time and then you discard them. These are usually inexpensive and require little to no maintenance. However, they will self-discharge over time, which means even when they are not in use, they will lose some of their charge. The discharge rate depends on the type of battery. Once discharged, they have a tendency to 'leak' and could damage the electronic device it is installed in. Examples of primary batteries are Alkaline and Lithium iron.

• Secondary batteries can be electrically recharged over and over, hundreds, and in some cases, thousands of times. These are usually more expensive and they all require the correct charging device. These also self-discharge over time, but since they are rechargeable, it's not that big of a deal. But it's still a good idea to know how fast each type of rechargeable battery will self-discharge so you have an idea of how often you should 'top them off.' Most rechargeable batteries do not suffer from the 'leaking' tendency that their primary counterparts experience. Examples of secondary batteries are Ni-Cad, NiMH, NiMH LSD, and Li-ion.

Battery Options:

Now that we've defined the types of batteries that are available, let's talk about the options available. The most common battery options are Alkaline, Ni-Cad, NiMH (standard and LSD- Low discharge), Lithium, and Lithium-ion.

• Alkaline batteries are the single use batteries you buy, use until they're dead, and then throw away. For years they were the only choice of household batteries, but with the advent of NiMH and Lithium batteries, they're not that great of a choice anymore. With very few exceptions, they are not rechargeable. Yes, they are cheaper up front, but you'll pay much more over time as you have to replace them each time they die. And everyone knows that if you leave an alkaline battery in a device for too long, they can corrode, leak, and damage or ruin the device it is in. One plus for alkaline batteries is their low self-discharge rate. This contributes to their decent shelf life (up to 10 years) and also makes them good for low-drain devices such as clocks and TV remotes. So as a general rule, I will use them for toys and low-drain devices such as tv remotes, but NEVER for any equipment I might need to really rely on in the future, such as any of my emergency preparedness equipment. 

• Ni-Cd refers to nickel cadmium batteries. They were great in their day as they were the rechargeable alternatives to alkaline. But there are much better alternatives now. So don't let the fact that they are inexpensive rechargeable batteries lure you into buying them. They have a long 'con' list. Such as, they have a high self-discharge rate - around 10% per month. So in less than a year, your Ni-Cd batteries will most likely be dead. They also have a terrible shelf life. Some can last for 5+ years, but they generally lose a lot of their capacity within the first 18 months. And remember the days when you were encouraged to drain your device completely before recharging it? Well, those devices were most likely using Ni-Cd batteries. Ni-Cds also suffer from "memory effect", which means they "remember" the previous discharge amount and won't give much more than that on the next charge cycle. So if you have a device that routinely gets drained down only 10% or so before it gets recharged back to full, that 10% range eventually becomes the entire capacity of that battery. Fortunately, Ni-Cd's have been mostly replaced with NiMH batteries, and therefore, they now rank down there with alkaline batteries, finding their way onto my personal "do not use" list, especially for emergency purposes.

• NiMH or Nickel Metal Hydride batteries are now among the most common rechargeable batteries out there. There are two types of NiMH batteries, with some major differences. So let's discuss them.

  • • Standard NiMH have come a long way since Ni-Cds, but they still have a few downsides. They have a huge self-discharge rate. Within the first 24 hours, they can lose about 20% of their charge, and then continue to lose 10% per month thereafter. They also shouldn't sit idle. They need to be regularly charged and recharged. If you don't do this, they can discharge beyond their recoverable point, and then they won't recharge at all. This makes them unsuitable for long-term storage and almost all emergency preps. Do not use these in your disaster preps. Right about now you're thinking, "Well, that's strike three. Which batteries can I use?" Well, don't worry, there's good news. Keep reading...

    • NiMH LSD batteries are Nickel Metal Hydride batteries with a Low Self-Discharge rate, and these solved the discharge problems that plagued the standard NiMH batteries. So I'll say it right now, these are the batteries you want to be using in your emergency preps. As the name implies, NiMH LSD batteries don't have a high self-discharge at all. When stored properly, they will retain up to 85% of their charge after 1 year and will still have 70% of their charge in 5 years. There is one catch with these batteries: the higher the capacity, the fewer times you can recharge it. For example, a 2500mAh NiMH LSD battery might only get 500 cycles, or charges, whereas a 2100mAh NiMH LSD battery could get up to 2100 cycles. So in the case of these batteries, the lower capacity battery is actually a better deal in the long run. Be aware that all NiMH batteries are sensitive to overheating and overcharging, so if you're going this route, you should use a smart charger that knows when to quit charging them, or at least a charger that indicates when they are fully charged so you can remove the batteries when they are full.

Now that I have you all convinced that rechargeable batteries are the only way to go, I'm going to introduce the Lithium battery. There are two types that I want to cover: the Lithium and the Lithium-ion. 

• Lithium batteries are not rechargeable, but they dominate in every other category and are the best choice for long-term storage and emergency preparedness in general, especially for 72-hour kits where batteries may be stored for years at a time with no use. Energizer makes one called the Lithium Ultimate and it is awesome. These batteries have a very low self-discharge rate, holding 80% of their charge for over 15 years, compared to the NiMH LSD which will retain only 70% up to 5 years. So this makes them a great choice of battery to throw into your 72-hour kit and literally forget about for years. They function well in high and low temperatures and have a shelf life of up to 20 years. Other than the fact that they are not rechargeable, the only other down-side is they are expensive, but this is because you are paying for all the up-sides. These are the best choice for batteries that you want to store long term and know they will still work when needed for that emergency. So between these and the NiMH LSD batteries, you should be fully covered.

• Li-ion or Lithium-ion batteries are the rechargeable version of the lithium battery. These are usually found in cell phones, laptops, and other consumer grade electronics. Even electric vehicles, such as the ones produced by Tesla, use Lithium-ion chemistry with LFP {Lithium Iron Phosphate} and NMC {Nickel Manganese Cobalt}. Li-ion batteries are often installed in devices that require very specialized or non-removable batteries. But there are some problems that actually make them less than desirable for some uses, especially emergency preparedness. First, they should not be discharged down to a zero charge. If they drop below a certain capacity, the battery can be ruined and will not recharge. They also have a high self-discharge rate at 15-20% per year. So they aren't a good choice to leave unused for long periods of time as they will eventually self-discharge beyond recovery. There are other drawbacks as well, but basically, li-ion batteries should really only be used for electronics with high energy requirements that get used, drawn down, and recharged periodically, as in the case of cell phones, laps, and electric cars. Because emergency equipment often sits dormant, you do not want to use Li-ion batteries in any of your emergency equipment.

Summary:

So basically, when it comes to emergency preparedness and battery storage/use, you probably want to be using some combination of rechargeable and non-rechargeable batteries. For your rechargeables, look for NiMH LSD batteries. For your non-rechargeable batteries that will probably be stored for several to many years, look for Lithium batteries. Below are some charts comparing the types of batteries' capacity, charging cycles, self-discharge rate, shelf life, and price.

Below is a chart comparing the cost of batteries based on individual battery price from least expensive to most expensive (as of Feb 2026). 

Below is a chart comparing the cost of batteries based on price per charge/use from least expensive to most expensive (as of Feb 2026). 

While Alkaline batteries are the most inexpensive (per unit), they are actually almost the most expensive (per use). The chart above illustrates this very well. A single alkaline battery from Costco costs about $0.52 whereas the Ni-MH LSD rechargeable battery is almost 6 times more expensive at $3.04 per battery. However, this is not the metric you want to be using to compare battery prices. If we compare how much it costs each time we use the battery, an alkaline battery costs $.52 per use (since they are a one time use and then discard) whereas, the NiMH LSD battery costs about $0.0014 each time we use it (since they can be recharged and reused up to 2100 times). So now, when we compare price per use, the originally cheaper alkaline battery is actually about 371 times more expensive than it's Ni-MH LSD counterpart. So as you can see, the "more expensive" rechargeable battery is actually tons cheaper than the "inexpensive" alkaline battery...in the long run.

Guidelines:

As a general rule, I use the NiMH LSD batteries in flashlights, led lanterns, and other emergency preparedness items that are more likely to see some regular household use, and I just have to remember to check or recharge them periodically. Additionally, I keep some lithium ultimate (non-rechargeable) batteries as backups in case recharging is no longer an option. As far as equipment that does not see regular use, such as electronics in your 72-hour kit or lights in your 'dark kit', I store primary lithium ultimate batteries with (but not installed in) the devices, and I keep some NiMH LSD as backups stored elsewhere in the kit. This way I know that my batteries will be ready when I need them, even if it has been many years. But if you choose to use NiMH LSDs, make sure you also store a charging device of some kind. I keep a USB charger with a small foldable solar panel in our 72-hour kits so I can recharge our NiMH LSD batteries. Any battery stored in your car (such as in your car kit) needs to be able to handle the summer heat inside a car. NiMH LSD batteries are much more susceptible to damage from heat than lithium batteries are, so I recommend storing lithium batteries in your car kits. Note: never store li-ion batteries in your car as they can explode in high heat.

My recommendations:

• Get some good NiMH LSD rechargeable batteries such as the Eneloop (AA: 2000mAh / AAA: 800mAh) or the Fujitsu (AA: 2000mAh or AAA: 800mAh).

• Have at least a few Ultimate Lithium Batteries (non-rechargeable) for long term storage.

• Have a good battery charger, such as the Eneloop charger by Panasonic. It will charge AA as well as AAA. These are around $29. Link here.

• Have a good battery checker on hand, such as the one made by Vtechology, so you can check the status of your batteries at any time. These cost around $6. Link here.

I hope this helps as you consider battery power for all your electronic devices.