Frequently Asked Questions

What increases the possibility for alkaline battery leakage?
Typically alkaline batteries will not leak under normal stoarage and/or usage conditions. The potential for leakage is significantly increased, however, if the batteries are subjected to charging, mixing of battery chemistries, mixing of fresh and used batteries, physical damage, extended exposure to high temperature or deep discharge.

Alkaline battery leakage is extremely caustic and contact with bare skin should be avoided. In the event that battery leakage comes in contact with your skin, flush the area for 15 minutes with copious amounts of water and seek medical attention.

How can I test batteries to see if they're still good?
A battery tester (loaded voltmeter) is a simple and effective way to determine if a battery is "good" or "bad." Most testers place an appropriate load on the batteries and then read the voltage. A voltmeter without a load can give very misleading information and is not recommended for this purpose. Note that testers are typically not capable of providing reliable run time estimates.

How long can I store batteries?
When stored at room temperature (i.e. 70°F/ 21°C), cylindrical alkaline batteries have a shelf life of approx. 5 years and cylindrical carbon last 2 years. Lithium Cylindrical types can be stored from 10 to 15 years. Prolonged storage at elevated temperatures will shorten storage life.

Why is mixing batteries of different chemistries, brands or age a potential problem?
Mixing of battery types (different chemistries, brands and/or fresh vs. used) in a device is not recommended and can significantly increase the potential for leakage and reduced device run time. The primary concern is an imbalance in capacities or available energy between the installed batteries. As the weakest battery becomes exhausted, it will be force discharged by the stronger batteries to very low or negative voltage levels which drastically increases the potential for leakage.

What type of batteries can be recharged?
Only batteries that are labeled as rechargeable are capable of being safely recharged. Attempting to recharge non-rechargeable batteries greatly increases the potential for leakage and rupture. Charging must be conducted in chargers specifically approved for each product type which may vary depending on brand and model of both battery and charger.

Battery Safety

What are the different types of rechargeable battery chemistries/technologies?
Batteries in portable consumer devices (laptops and notebooks, camcorders, cellular phones, etc.) are principally made using Nickel Cadmium (NiCd), Nickel Metal Hydride (NiMH) or Lithium Ion (Li-Ion) technologies. Each type of rechargeable battery technology has its own unique characteristics.

What is the "Memory Effect"?
NiCd batteries, and to a lesser extent NiMH batteries, suffer from what's called the "memory effect."  If a NiCd battery is partially discharged on a continuous basis before re-charging, the battery "forgets" that it has the capacity to further discharge all the way down. To illustrate: If you fully charge your battery every time, and then use only 50% of its capacity before the next recharge, eventually the battery will lose its extra 50% capacity which has remained unused. Your battery will remain functional, but only at 50% of its original capacity. The way to avoid "memory effect" is to fully cycle (fully charge and then fully discharge) your battery at least once every two to three weeks. Batteries can be discharged by unplugging the device's AC adaptor and letting the device run on the battery until it ceases to function. This will insure your battery remains healthy.

What does NoMEM® mean?
Batteries that have been manufactured using the "sintered" method of active-material drying will not be affected by the conditions that cause "memory effect." 

Is it possible to upgrade my device's battery to a newer chemistry?
NiCd & NiMH versus Li-ion are fundamentally different from one another and cannot be substituted unless the device has been pre-configured from the factory to accept more than one type of rechargeable chemistry.  NiCd and NiMH are very similar, except in capacity and charge rate.  But those two differences preclude using the same charger on both.  It is best to use the chemistry your device was designed for. Refer to your owner's manual to find out which rechargeable battery types your particular device supports, or simply use our BatteryFinder to find your device. It will automatically list all of the battery types supported by your machine.

My new battery isn't charging. Why is that?
New batteries are shipped in a discharged condition and must be charged before use. We generally recommend an overnight charge (approximately twelve hours). Refer to your user's manual for charging instructions. Rechargeable batteries should be cycled - fully charged and then fully discharged - 2 to 4 times initially to allow them to reach their full capacity. (Note: it is perfectly normal for a battery to become warm to the touch during charging and discharging).

New batteries are hard for your device to charge; they have never been fully charged and are therefore "unformed." Sometimes your device's charger will stop charging a new battery before it is fully charged. If this happens, simply remove the battery from your device and then re-insert it. The charge cycle should begin again. This may happen several times during your first battery charge. Don't worry; it's perfectly normal.

Should I recycle my old battery? How?
NiCd, NiMH and Li-ion batteries should be recycled. Be environmentally conscious - do NOT throw these batteries in the trash.

If you don't know where your local recycling facility is, call the Portable Rechargeable Battery Association at 1-800-822-8837. They will provide you with the address of the recycling center nearest to you.

Are cylindrical alkaline batteries considered hazardous waste?
In the United States and many other countries cylindrical alkaline batteries are classified as common household waste. Great strides have been made in making alkaline batteries more environmentally friendly which have been manufactured free of added mercury since the mid 1990's. Classification details may vary and should be confirmed in each specific geographical location.

Does rapid charging reduce the life of batteries?
No.  Fast chargers will simultaneously rapidly charge and condition the battery thus extending the life of the battery. Overcharging and overheating a battery will adversely affect the life and performance of a battery.

Which are better, NiCd or NiMH batteries?
For most electronic devices it is better to use NiMH batteries than NiCd batteries. NiCd batteries use cadmium, a toxic heavy metal that can damage the environment if not disposed of properly. (They should be recycled not discarded). Compared to NiCd, NiMH batteries have a higher capacity in a more compact battery and experience less memory effect.

Can NiMH batteries be substituted for alkaline batteries?
Some devices are marked for specific battery chemistries.  Check inside the battery compartment of your device or your user manual to make sure they are compatible. Note the discharge curve of alkaline batteries continuously reduces voltage level. In fact, over the course of their discharge, alkaline batteries average about 1.2 volts. The main difference is that an alkaline battery starts at 1.5 volts and gradually drops to less than 1.0 volts. NiMH batteries stay at about 1.2 volts for almost 80% of their discharge cycle. Once alkaline batteries discharge to 50% capacity, it will be delivering a lower voltage than a NiMH battery.

Why don't my AA rechargeable alkaline batteries last in my digit camera?
Alkaline batteries are best suited for low drain personal electronic devices such as toys, portable radios, CD players and television remote controls. A digital camera is a high drain device, which in turn requires a higher drain battery with greater capacity.  The best battery for digital cameras is a Lithium Iron AA.

Does putting batteries in the freezer or refrigerator make them last longer?
No, storage in a refrigerator or freezer is not required or recommended for batteries produced today. Cold temperature storage can in fact harm batteries if condensation results in corroded contacts or label or seal damage due to extreme temperature storage. To maximize performance and shelf life, store batteries at normal room temperatures (68°F to 78°F or 20°C to 25°C) with moderated humidity levels (35 to 65% RH).

How many times can a rechargeable battery be recharged?
The number of times a battery can be recharged depends on many factors. These include the discharging drain load, the frequency of use, the length of time in a discharged state, charge temperature and conditioning. Rechargeable batteries do NOT last forever and need to be replaced eventually.

How long do batteries last (what is the life span of my new battery)? 
The life of a rechargeable battery operating under normal conditions is generally between 500 to 800 charge-discharge cycles. This translates into one and a half to three years of battery life for the average user. As your rechargeable battery begins to die, you will notice a decline in the running time of the battery. When your two hour battery is only supplying you with an hour's worth of use, it's time for a new one.

When is it time to replace my battery?
When you notice run time being approximately 50% less than the run time when the battery was new, we recommend that you replace the battery with a new battery. Rechargeable batteries do not last forever and need to be replaced eventually.

How long will my batteries last in a device?
There are several factors that impact length of service or run time. The most important aspect is the rate at which the device consumes power. A high drain device such as a digital camera will deplete a battery faster than a low drain device like a clock. Other factors affecting overall battery performance are environmental conditions, device usage patterns (continuous or intermittent) and battery size/chemistry.  The proper charger for the cell is an absolute necessity.

Can I store my battery on my charger or camera?
It is advised to remove the battery from the camera or battery charger when it is not being used for long periods of time. Small amounts of current flow through the battery even when it is not in use. The battery may become drained and lose its capacity. We also recommend that you fully charge your batteries before storing them for long periods of time.

Can I overcharge a battery?
Yes, putting too much charge energy in the cells can damage batteries.  Some batteries have protective circuitry to prevent overheating.

Battery Performance

Breaking In New Batteries - New NiCd and NiMH batteries come in a discharged condition and must be fully charged before use. It is recommended that you fully charge and discharge your new battery two to four times to allow it to reach its maximum rated capacity.  Small sealed lead-acid batteries do not come discharged, but must be fully recharged before being put to use.

Preventing the Memory Effect - Keep your battery healthy by fully charging and then fully discharging it at least once every two to three weeks. Exceptions to the rule are Li-Ion batteries and Sealed Lead-Acid batteries which do not suffer from the memory effect.

Keep Your Batteries Clean - It's a good idea to clean dirty battery contacts with a cotton swab and alcohol. This helps maintain a good connection between the battery and your portable device.

Battery Storage - If you don't plan on using the battery for a month or more, we recommend storing it in a clean, dry, cool place away from heat and metal objects. NiCd, NiMH and Li-Ion batteries will self-discharge during storage; remember to break them in before use. Sealed Lead Acid (SLA) batteries must be kept at full charge during storage. This is usually achieved by using special trickle chargers. If you do not have a trickle charger, do not attempt to store SLA batteries for more than three months.

For Notebook Users - To get maximum performance from your battery, fully optimize the notebook's power management features prior to use. Power management is a trade off: better power conservation in exchange for lesser computer performance. The power management system conserves battery power by setting the processor to run at a slower speed, dimming the screen, spinning down the hard drive when it's not in use and causing the machine to go into sleep mode when inactive. Your notebook user's guide will provide information relating to specific power management features.

Notebooks

How long will the new battery power my laptop?
That is difficult to determine. Actual battery running time depends upon the power demands made by the equipment. The use of the monitor, the hard drive and other accessories results in an additional drain upon the battery effectively reducing its running time. The total running time of the battery is also dependent upon the design of the equipment. Generally, a new battery will run at least as long (and usually longer) as your old battery did when it was new.

What is a "smart" battery?
Smart batteries have internal circuit boards with smart chips which allow them to communicate with the notebook and thus better monitor battery performance, output voltage and temperature. Smart batteries will generally run 15% longer due to their increased efficiency and also give the computer much more accurate "fuel gauge" capabilities to determine how much battery running time is left before the next recharge is required.

Do I need to charge my new laptop or notebook battery?
A new battery comes in a discharged condition and must be charged before use (refer to the devices manual for charging instructions). Upon initial use (or after a prolonged storage period) the battery may require three to four charge/discharge cycles before achieving maximum capacity. When charging the battery for the first time the device may indicate that charging is complete after just 10 or 15 minutes. This is a normal phenomenon with rechargeable batteries. Remove the battery from the device, reinsert it and repeat the charging procedure.

Technical Questions

What is a deep cycle battery?
Deep cycle batteries are designed to be discharged down as much as 80% time after time, and have much thicker plates than that of a standard battery.

What is a gel cell battery?
A gel battery design is typically a modification of the standard lead acid automotive or marine battery. A gelling agent is added to the electrolyte to reduce movement inside the battery case. Many gel batteries also use one way valves in place of open vents, this helps the normal internal gasses to recombine back into water in the battery, reducing gassing. "Gel Cell" batteries are non-spillable even if they are broken. Gel cells must be charged at a lower rate (max C/5) and voltage than flooded or AGM to prevent excess gas from damaging the cells. Fast charging them on a conventional automotive charger may permanently damage a gel battery.   NEVER charge either AGM or GEL sealed lead-acid batteries with an automotive charger.  The charger will damage the batteries.

What is a milliamp hour (mAH)?
Milliamp Hour is a term used to describe the capacity of a battery or the rate of discharge it is experiencing.  The capacity of various chemistries is expressed in milliamp hours for smaller batteries and amp/hours for larger batteries; discharged over a specific period of time expressed in hours.  The combination of the discharge rate (milliamp hours or amp hours), and the time to complete discharge, determine the capacity of the battery.

How is the rated capacity of a battery determined?
The capacity of a battery is typically expressed in milliamp-hours (mAH) or amp hours. For primary batteries, samples are discharged at a specific current drain (i.e. 25mAH) and time recorded to a cutoff voltage (i.e. 0.8 volts). The time (hours) it takes the battery to reach the cutoff voltage is then multiplied by the current drain to establish the mAH capacity of the battery. Rechargeable batteries (NiMH) are rated based on a C/10 charge followed by a C/5 discharge.  Sealed Lead-Acid batteries are rated on a C/20 charge and discharge rate.

If the milliamp hours  (mAH) of my current battery are rated differently than the mAH of the replacement battery, will it still work in my device?
Yes, it will work. The mAH is a measurement to compare run times. For example, a battery with a 2500mAH rating would last twice as long as a battery with a 1250mAH rating.

Can batteries freeze?
In a partially discharged state, the electrolyte in a lead acid battery may freeze. At a 40% state of charge, electrolyte will freeze if the temperature reaches approximately -16.0°F. The freezing temperature of the electrolyte in a fully charged battery is -92.0°F.

Do batteries self-discharge when not in use?
All batteries, regardless of their chemistry, self-discharge. The rate of self-discharge depends both on the type of battery and the storage temperature the batteries are exposed to. However, for a good estimate, deep cycle AGM or GEL batteries self-discharge approximately 3% per month, stored at 25°C (77°F).

What is the difference between a NiCd and NiMH chemistry battery?
The main difference between the two is the fact that NiMH batteries (the newer of the two technologies) offer higher energy densities than NiCd batteries. In other words, pound for pound, NiMH delivers approximately twice the capacity of its NiCd counterpart. What this translates into is increased run-time from the battery with no additional bulk to weigh down your portable device. NiMH also offers another major advantage over NiCd.  NiCd batteries contain cadmium, a toxic heavy metal that must be recycled.  NiMH does not contain any toxic components, and can be disposed of in the trash.  However, the "green" movement encourages the recycling of all battery chemistries.

What is a lithium ion (Li-Ion) battery?
Li-Ion is a rechargeable chemistry that has quickly become the emerging standard for portable power in consumer devices. Li-Ion batteries that contain the same energy as a comparable NiMH battery will weigh approximately 35% less. This is crucial in applications such as camcorders or notebook computers where the battery makes up a significant portion of the device's weight.  This translates in to much longer run-times for the devices for the same weight.

What is the difference between carbon-zinc and alkaline batteries?
The term Super Heavy Duty (SHD) refers to the zinc chloride carbon zinc (CZn) chemical system which has largely replaced the LeClanché CZn "General Purpose" chemical system. Alkaline batteries are very similar to carbon-zinc, but are alkaline manganese dioxide chemistry, and contain about twice the power of a comparably sized carbon-zinc.  Carbon-zinc batteries are best suited for low drain applications such as clocks and simple smoke alarms or short intermittency devices such as remote controls.  Alkaline batteries are more suited to higher drain uses, like in toys, CD players, etc.

Why doesn't my flashlight work well in cold weather?
Alkaline and carbon-zinc batteries contain a water based electrolyte. As the battery temperature approaches the freezing point of water (32°F or 0°C) chemical reactions within the battery slow down due to reduced ion mobility. Ion mobility defines the ability of electrons to freely move, critical to the generation of electricity through a chemical reaction. The net result is a reduction in overall performance or run time which can be recovered as temperatures approach typical room conditions (68°F to 78°F or 20°C to 25°C).

Does the capacity of a battery change with the drain rate?
A battery is typically much more efficient at lower current drains. Therefore, available capacity will drop significantly as drain rates and/or the voltage functional endpoint increases.

SLA Battery Article

Why did my lead-acid battery swell up?

Most of the time, this problem happens to sealed lead-acid batteries of either AGM (Absorbed Glass Mat) or GEL (gelled electrolyte) construction. These battery constructions are known as "recombinant" batteries, referring to the absorption of gasses generated by the chemical process of the battery.  In order to absorb these gasses, the positive and negative plates must be as close together as possible and are usually only held apart by the thickness of the separator.  A consequence of the necessity of gas absorption, the pack of plates (the element) is inserted very tightly into the cell cavity, resulting in a lack of space for any other components. In the situation of a swollen battery, the cell plate components expanded, and the force exerted on the case caused it to swell and most likely split at numerous points.

The expansion of the cell element is as a result of internal heat, and can be as a result of either overcharging of the battery or from a drastic shorting of the battery terminals.  Either one of these situations will generate internal heat in the battery. Additionally, elemental lead natural has a high expansion rate when exposed to heat.  Since the cells of a battery of AGM or GEL construction are deliberately manufactured with no extra room, the result is the individual cell casings will split from expansion pressure, and deform from high heat, destroying the battery due to the massive damage to internal parts.

This usually does not happen to the battery alone; usually the battery was either shorted or overcharged. The overcharging of the battery can be the result of a charger that is delivering too much current to the battery, or a charger of higher voltage than the battery was accidentally used-for example a 12V charger on a 6V battery.    Regardless of the cause, the result is almost always the same; swelling and the destruction of the battery.

To avoid this particular accident, the end-user must consider the following points:

1)      Is this charger meant to be used on this type battery?
2)      Is this charger the right voltage for the battery I want to charge?
3)      Is the maximum current of this charger within the charging range of this battery?
4)      Do I have the right polarity connection between battery and charger?
5)      Are the battery terminals shielded from possible shorting?

These questions must be considered to not only avoid the destruction of a battery, but also for personal safety because in worst case scenarios the heat could cause the battery to catch fire.  Batteries are active devices and are reactive, not proactive, so they respond to the outside influences.