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Can i replace NiMH with lithium-ion?

In most cases, NiMH-batteries (Nickel Metal Hydride batteries) and lithium-ion batteries aren’t interchangeable. They have different shapes, sizes and voltages most of the time. Sometimes a device can accept both, but this will most likely be mentioned on the product or in the manual.

Can you overcharge a NiMH battery?

NiMH batteries (Nickel Metal Hydride batteries) are more sensitive to overcharging, compared to NiCd batteries. Overcharging NiMH batteries can lead to several issues, like reduced performance and lifespan. In more severe cases, the battery can expand and leak.


You can prevent overcharging by using the proper charger. Most manufacturers of NiMH batteries (Nickel Metal Hydride batteries) recommend a certain charger for their batteries. You can also pay attention to the charging time and make sure avoid high temperatures while charging.

Do NiMH batteries have memory effect?

NiMH batteries, short for Nickel Metal Hydride batteries, are largely immune to the ‘memory effect,’ making them low-maintenance and needing little special attention. They are also environmentally friendly, lacking heavy metals in their composition.

How long do NiMH batteries hold a charge?

Most NiMH-batteries (Nickel Metal Hydride batteries) will lose their charge over a peroid of time when they aren’t being used. At regular room temperature, they will lose about 1% of their charge per day. That means that they will generally retain 70% of their charge after 30 days.

How long do NiMH batteries last in storage?

It is possible to store charged NiMH-batteries (Nickel Metal Hydride batteries), but they will lose their charge over a period of time. At regular room temperature, they will lose about 1% of their charge per day. That means that they will generally retain 70% of their charge after 30 days.

How long do NiMH batteries take to charge?

The charging time for NiMH-batteries (Nickel Metal Hydride batteries) can differ depending on factors like the capacity of the battery and the charger’s charging rate. We recommend referring to the specific charging instructions provided by the manufacturer of the batteries and the charger to ensure safe and efficient charging.

How long do NiMH rechargeable batteries last?

The lifespan of a NiMH-battery (Nickel Metal Hydride) can vary depending on several factors. In terms of charge cycles, low-capacity AA-batteries of to 2000 mAh can be charged up to 1000 times. Higher capacity batteries, like 2500 mAh batteries can only be charged for about 500 times.

How long to charge a NiMH battery?

The time that it takes for a NiMH-battery to charge may vary on factors like the capacity of the battery and the charger’s charging rate. We recommend referring to the specific charging instructions provided by the manufacturer of both your charger and batteries.

Lithium-ion versus NiMH

NiMH-batteries (Nickel Metal Hydride batteries) have certain drawbacks when compared to lithium-ion batteries. One drawback is the need for NiMH-batteries to be discharged once every two months. Li-ion batteries have several advantages over NiMH batteries. They demand no maintenance, suffer from no memory effect, undergo less self-discharge, and are marginally more compact due to their superior energy density. It’s worth mentioning that Li-ion batteries are more susceptible to heat.

What is a sodium-ion battery?

A sodium-ion battery (also known as a saltwater battery) is a unique electrochemical energy storage system, based on saltwater electrolyte. Fundamentally, a saltwater battery comprises salt and a freshwater reservoir. During its operation, the salt- and freshwater are segregated, prompting the migration of sodium-ions from one side to the other. This ion flow generates an electric current, suitable for powering various devices. A saltwater battery offers low-maintenance, eco-friendliness, and versatility for diverse applications. It boasts a lifespan of up to 20 years.

Are sodium-ion batteries recyclable?

Yes. Unlike most batteries, sodium-ion batteries aren’t made from heavy metals. This makes them easier to recycle. As a result, they also give less impact on the environment.

Are sodium-ion batteries safe?

Sodium-ion batteries are made of a safe electrolyte: saltwater. The batteries are completely sealed and require no maintenance. They are self-balancing and therefore require no compensating charge or battery management system (BMS).

Will sodium-ion replace lithium?

Sodium-ion batteries are seen as a potential replacement for lithium-ion batteries in the future. This is because of the abundance of sodium resources and environmental impact. However, the larger size of sodium ions makes for a challenge. Lithium-ion is therefore still the preferred choice for situations where minimal size and weight are needed. The larger size of sodium-ion batteries make them limited in applications like laptops and smartphones.

What is the service life of a NiMH battery?

NiMH batteries are known to have a high capacity, measured in the number of (charge) cycles of the battery. For NiMH batteries, this is typically between 700 – 1000 cycles.

If the NiMH battery is repeatedly deeply discharged, performance starts to decline after 200 to 300 cycles. On average, NiMH batteries have a lifespan of about 2 to 3 years.

Are NiCD and NiMH batteries interchangeable?

NiMH and NiCd-batteries are both ideal for high-demanding devices. Since the import of NiCd-batteries has been banned in 2006, NiMH-batteries stand as a great alternative to NiCd. Typically, they have the same nominal voltage of 1.2 volts per cell, making them interchangeable in most cases.


An advantage of NiMH-batteries is that they generally have a higher energy density compared to NiCd-batteries. This makes NiMH-batteries last longer in some cases compared to their NiCd-counterpart.


NiCd and NiMH-batteries have different charging characteristics. NiMH batteries are more sensitive to overcharging. That’s why we recommend using only a designated NiMH charger to charge NiMH-batteries.

Where do I buy a sodium-ion saltwater battery?

Of course, Elfa has the sodium-ion battery in its range. Visit our saltwater batteries page for more information.

How does a sodium-ion saltwater battery work?

The sodium-ion battery works on a very simple principle: a plastic crate is filled in two compartments. A sodium-ion battery contains a salt and a freshwater reservoir. On contact, an electric current is created. When the battery charges, the fresh and salt water are separated again. The battery also contains manganese oxide and carbon-titanium phosphate.


A sodium-ion battery is low-maintenance, environmentally friendly and lends itself well to domestic use. The saltwater battery has a service life of up to 20 years.

What is the difference between IECEx and ATEX?

ATEX is driven by EU legislation, while IECEx is a voluntary certification scheme. However, both provide an acceptable way to demonstrate compliance with IEC standards. The difference between ATEX and IECEx is initially that ATEX is only valid in the EU and IECEx is accepted worldwide. Look here for more information about ATEX.

What are disadvantages of rechargeable batteries?

  1. Rechargeable batteries will at some point stop working. If, for example, you are on a reportage with your camera (winder, flash), you could get a rather abrupt surprise. Alkaline batteries lose their voltage more slowly and stop working more gradually.
  2. They are somewhat more expensive than alkaline batteries, also because you have to buy a charger.
  3. Rechargeable nickel-cadmium batteries contain 15% of the heavy metal cadmium, however, they can be recycled excellently.
  4. NiCd has the disadvantage that you have to fully discharge them first before you can recharge them, otherwise a memory block will soon form and you will not be able to fill them up again. NiMH batteries do not experience this, so you can (re)charge them at any time.

Can a 1.2 Volt rechargeable battery be used for everything?

Most of the time. Alkaline batteries only have a capacity of 1.5 volts at the beginning of use, but this soon drops and eventually it even falls below the level of a rechargeable battery. Rechargeable batteries, on the other hand, have a very stable voltage course.

What are the abbreviations for battery systems?

These are the common abbreviations for the battery systems. These are the terms that are universally used and you can also find them in this product catalogue. A round battery (see table) is round and flat. A P is the designation for all batteries that are not round. Many chemical abbreviations may therefore be followed by an F (flat) or a P, in addition to an R.


B = Lithium carbon monofluoride (low drain) BR
C = Lithium mangaan dioxide (high drain) CR
E = Lithium thionyl chloride ER
F = Lithium iron disulfide FR
G = Lithium Copper oxide GR
K = Cadmium KR
L = Alkaline LR
M = Mercury MR
P = Oxygen PR
S = Silver SR


An LR battery is a round alkaline battery. So a flat alkaline battery would become an LF battery and so on.

What are the main advantages of rechargeable batteries?

They last extremely long because they can be recharged a thousand times. Although they are more expensive to buy than non-rechargeable alkaline batteries, if you use batteries regularly, the investment in the battery and charger will pay for itself very quickly. So you don’t have to keep going back for a new set of batteries.


Because rechargeable batteries last longer, the amount of alkaline batteries going into waste is reduced, which is better for the environment. Ask in advance whether your application is suitable for using rechargeable batteries.

How does a rechargeable battery work?

You can compare the operation of a rechargeable battery with a battery of a car. When it’ s empty, it can be recharged and used again. With the best possible treatment, these batteries can be recharged up to thousands of times. Because of its constant power (1.2 Volts), a rechargeable battery has virtually the same power from start to finish. Then it stops quite suddenly and has to be loaded.

What do I need to know about air-alkaline batteries?

A distinctive system within the various primary battery types is air-alkaline. The battery uses oxygen (O2) from the air as its cathode. The oxygen is led through holes in the casing to the cathode where reduction (absorption of electrons) takes place on a carbon layer. Because the battery casing only has to house an anode, the energy density per weight is on average high, between 220-300 Wh/kg (compared to 99-123 Wh/kg for a silver-oxide battery).


An additional advantage of this battery is its relatively low cost and environmentally friendly character. These batteries have an infinite storage time until they are activated by exposing them to air. After activation, the shelf life is rather short due to high self-discharge. Another disadvantage: once activated, the chemical process of energy production cannot be stopped, but it can be slowed down.


Applications of air-alkaline batteries:


  • Railway signal lighting
  • Road signal lighting
  • Buoyancy and signal lighting at sea
  • Telecommunications
  • Parking meters
  • Fencing

Can alkaline batteries be recharged?

No, not the normal alkaline batteries. Rechargeable alkaline batteries do exist, but they have major disadvantages:


  • Firstly, you need a special charger, which is usually relatively expensive. Charging alkaline batteries in chargers intended for genuine nickel-hydride and nickel-cadmium rechargeable batteries can be very dangerous (explosion risk).


  • Secondly, the voltage of an alkaline battery can quickly drop below a critical point, after which it cannot be recharged. The problem is that while using it, you do not know when this point has been reached. So you have to recharge quickly, which is a disadvantage if you want to use the device for a longer period of time.


  • Thirdly, when you recharge alkaline batteries, you never get the full capacity back. Once the batteries have been used several times, the available energy quickly becomes less and less. In theory, you will be able to reload them a few dozen times at most. However, the net return is very small. Because of these disadvantages, it is better to buy actual rechargeable batteries. The only advantage in charging alkaline batteries is the higher initial voltage. But this voltage drops at a certain point even below that of real rechargeable batteries.

What types of non-rechargeable batteries are there?

Alkaline batteries, lithium batteries and specialist batteries such as Air-alkaline and ZincAir-alkaline. Alkaline batteries are often affordable and ideal for applications where power consumption is generally low. Lithium batteries last up to 7 times longer and can provide higher peak power. More information on the different types of non-rechargeable batteries (primary batteries) can be found here.

What affects the life of primary batteries?

The main factors for this are the chemistry of the battery, ambient temperature and energy consumption of the application.


Read more information here.

What is a nickel cadmium battery?

This is a type of battery invented in 1899 by Waldmar Jungner. Some characteristics:


  • The battery is very robust and can be recharged quickly with little effort.
  • Performs well at low temperatures


Click here for more details on nickel cadmium batteries.

What is a lithium iron phosphate battery?

A lithium iron phosphate battery is a battery type that features a chemistry that has been around since 1996. A number of characteristics are mentioned below:


  • Lithium iron phosphate batteries can be charged rapidly up to 100%.
  • Stores energy better than most other lead-acid batteries (100% instead of 85% with other lead-acid batteries)


Click here for more information on lithium iron phosphate batteries.

What is a lead-acid battery?

A lead-acid battery is the most commonly used type of battery. Lead-acid batteries have several advantages:


  • They have a simple design
  • Have a generally low price
  • Are suitable for various applications such as telecommunications, data centres, railways, defence and security systems


Click here for more information on lead-acid batteries.

What are alkaline batteries?

Alkaline batteries are the most commonly used type of batteries. There are a number of characteristics of this type:


  • They have a low purchase price
  • The alkaline batteries deliver a lot of energy even at low temperatures
  • Alkaline batteries have a low self-discharge rate


For more information on these types of batteries, click here.

What are lithium batteries?

These are a particular type of batteries that have a number of distinguishing features:


  • Lithium is a good solution when high peak power is required.
  • They last on average 7 times longer than alkaline batteries.
  • Lithium works at temperatures of -20 to +40 degrees.


Lithium batteries are characterised by their extremely low self-discharge. The self-discharge per year is only 1% of the capacity. The voltage of this battery is exceptionally high. This information sheet lists a number of brands that produce lithium batteries and the various product variants that come with them. Lithium is a light metal with an exceptionally high capacity (3.86 Ah/gram). When lithium is mixed with other chemicals such as manganese or sulphur, the result is a battery with high energy, low weight, reduced self-discharge and the ability to perform under extreme conditions.


Applications of lithium batteries


Lithium is used in a wide range of applications, from mobile phones and microprocessors to large industrial workplaces such as in the oil and gas industry and in space.


For more information about lithium batteries, click here.

What is the most frequent battery?

The most commonly used battery is the lead-acid battery. This is because of the simple construction of the battery and a generally low price. For more information on this battery type, as well as a recommendation of a brand that offers interesting lead-acid batteries, click here.

What are the most common types of batteries?

The most commonly used type of batteries are alkaline batteries. Providing a lot of energy is an important feature (also at low temperatures). They are often used for devices that consume less power for a long time. Click herefor more information about alkaline batteries and other types.

What is the difference between a nickel cadmium battery and a nickel metal hydride battery?

Nickel cadmium batteries and nickel metal hydride batteries have some interesting differences from each other:
– Nickel metal hydride batteries have up to twice the capacity of nickel cadmium batteries.
– Nickel cadmium batteries often suffer more from the ‘memory effect’ than nickel metal hydride batteries.
– Nickel-metal hydride batteries require less maintenance and care.


The nickel metal hydride battery can be considered the development on the nickel cadmium battery. For more details, click here.

What is the difference between a lithium and an alkaline battery?

There are several differences between a lithium and an alkaline battery. The most important ones are summarised below:

  • Lithium batteries generally last 7 times longer than alkaline batteries.
  • Alkaline batteries are usually more affordable than lithium batteries
  • Lithium batteries are often used for professional purposes, while the alkaline varieties are mainly used for consumer devices such as remote controls and radios.


For more information about Alkaline and Lithium batteries, click here.

Where can I find more information about ATEX?

There is a lot of information available. Most of the information can be found here.


Here are some more interesting websites as well:

Which ATEX zones are distinguished and what do they mean?

ATEX refers to danger zones.


The ambient atmosphere and the prevailing conditions at the workplace are decisive for the installation methods of the equipment to be used and the choice of the work equipment to be used. It is therefore a prerequisite that a danger zone classification is carried out of the areas that could be dangerous from the point of view of gas and dust explosion danger.

These potentially hazardous areas are divided into danger zones according to the frequency and duration of occurrence of an explosive atmosphere:


  • Zone 0, 1 and 2: in the event of a gas explosion (a mixture of flammable gas, vapour or mist with air).
  • Zone 20, 21 and 22: at the risk of a dust explosion (a cloud of combustible dust).

The lowest number indicates the most dangerous zone. The higher the classification of a danger zone, the more demanding are the requirements for the design of the working environment and for the application and use of equipment and protective systems. For more information on ATEX, click here.

Where does ATEX stand for?

ATEX stands for ATmospheres EXplosives, or explosive atmospheres.


An explosive atmosphere is defined as a mixture of flammable substances in the form of gases, fumes, mists and dusts under atmospheric conditions, in which combustion spreads to the entire mixture after ignition.

Since July 2003 ATEX 95 and ATEX 137 have been introduced; directives that were specifically written to focus attention on safety in explosive areas and make the use of explosion-proof products legally binding in such areas.

The guideline applies to all companies in which “a dangerous explosive atmosphere may occur as a result of the use of flammable substances”. For more information on ATEX, click here.

Which ATEX codes are distinguished?

Whether a lamp is ATEX certified or not can be seen on the lamp housing. The certification is printed in it. This consists of a number of codes. These codes and their meanings are listed below:


  • CE: This code confirms that the product complies with all EU quality requirements.
  • Ex: The specific sign for explosion prevention.
  • G, D or GD: Applicable in gas (G), dust (D) or both (GD) atmospheres.
  • E Ex: Approved for use in explosive areas in accordance with the latest common European requirements.
  • E ib: Level of protection.
  • IIA, IIB or IIC: The gas group to which the product belongs. (IIA has the lowest risk of ignition, IIC the highest).
  • T1 to T6: Temperature classification of the used light bulb. Classification according to the maximum temperature of the surface, with T1 being the highest and T6 the lowest.


An ATEX certification should be issued by a notified body such as KEMA or DEMKO. If the lamp is evaluated by a non-certified testing institute, the zone in which the certification is granted is maximum 2. This is the lowest protection class. For more information on ATEX, click here.

What are ATEX certified lights?

ATEX stands for ATmospheres EXplosives, or explosive atmospheres. If a lamp is ATEX-certified, this means that it is suitable for use in an explosion-hazardous environment. Whether a lamp is ATEX certified or not can be seen on the lamp housing. The certification is printed in it. Elfa has these ATEX certified lights from a number of leading brands in its range. Look here for more information.

What are light bulbs?

An light bulb consists of a vacuum-drawn or glass-filled glass bulb containing a filament. When current flows through the filament, it starts to glow and emit light. There are different types of bulbs for different applications. This depends on the type of noble gas added to it. In general, we speak of 3 types of light bulbs: the ‘normal’ (krypton) light bulb, the halogen light bulb and the xenon light bulb.


  • Krypton light bulb 90 to 95 percent of the electricity used by a light bulb is converted into heat. This means that only 5 to 10 percent of the energy is actually converted into light. So an incandescent light bulb is not very efficient. Light bulbs are the least energy-efficient and have an average burning time of 1,000 hours.
  • Halogen light bulb The halogen light bulb is a type of incandescent lamp that produces extra light thanks to the halogen gas. It also lasts longer than a normal light bulb and the consumption for some applications is also 30% lower. Although the halogen lamp is more expensive, it distinguishes itself from other bulbs through its high light output and excellent colour rendering. Moreover, the performance is constant for almost the entire lifetime and halogen lamps are often smaller than ordinary light bulbs.
  • In the case of Xenon bulbs and lights, gas is ignited. Due to gas discharge in the xenon lighting, an arc is created that has up to 3x more light output than an ordinary halogen lamp. After approximately 2,500 hours, the light output is still about 70%, which is still more than a good halogen lamp.

What are the differences in fittings?

There are a large number of possible fittings for the various lights. Here are the most common:

  • Screw fittings: The best known are the small (E14) and the large (E27). We also know the Goliath fitting (E40).
  • Plug fittings: This means that the bulb has one or more feet, allowing it to be inserted into the socket in one movement. It usually clamps the foot(s) automatically, but sometimes it needs to be screwed. Plug fittings are available from very small to quite large.
  • TL fittings: Straight fluorescent tubes have their own fitting systems.
  • Bayonet fittings: These fittings are pushed into the lamp so that the pins on the side can get caught behind an opening.

What is LED lighting?

LED stands for Light Emitting Diode, and is seen as the light system of today and the future.

LEDs can be seen as the successors of light bulbs. Light bulbs have the disadvantage that after some time the filament burns out. This is different with LEDs, because they do not use a filament.

LEDs convert the power directly into light. This way, less power is consumed. The wire must glow first with a normal lamp. Another advantage is the much longer lifetime of LEDs. An LED can burn for more than ten years without breaking down.


The advantages of LEDs:

  • Energy-efficient: lots of light with a minimum of energy.
  • Extremely long lifetime (20,000-100,000 hours)
  • LEDs are virtually impossible to break down and are resistant to vibration, as they lack a delicate filament.
  • Can handle differences in temperature.
  • Lenses can be used to ‘play’ with the light beam from an LED. For example, one can make the beam wider or smaller.


Disadvantages (especially for ‘older’ LEDs):

  • The colour of the light tends to blue

How long do hearing aid batteries last?

That depends on the type and intensity of use. In general, the large battery type 675 lasts about three weeks, while the smallest batteries (the 5 and 10) only last a few days.

How do you know which hearing aid battery you need?

The sizes of hearing batteries can be recognised by the sticker on the battery pack. Hearing batteries are usually packed in blisters of 6 pieces, as follows:


Application Battery Colour

5 red Mini devices in the ear canal

10 yellow Mini devices in the ear canal

13 orange Appliances behind the ear and in the auricle

312 Brown Devices in ear canal

675 blue Gears behind the ear

Where is the plus and minus pole of a coin cell?

The negative pole is on the top and the positive pole on the slightly wider bottom. The plus side often shows the brand and type number; this side is almost always on top when inserting the battery.

Are there rechargeable coin cell batteries?

There are various types of rechargeable batteries. They are usually built into the various devices. They are rarely available in shops, partly due to the low demand.

Can coin cell batteries withstand high and low temperatures?

The maximum permissible temperatures for a battery are -55° and +125° Celsius. However, the best working environment for most cells is one where temperatures are between +10° and +35° Celsius.

Why is there a sticker on a zinc-air battery?

It is only when you take the sticker off this battery that the air activates it. Oxygen penetrates the battery through holes. Because the activated material comes from outside, there is more room in the battery for capacity. This way, the lifetime is long and the discharge curve is flat. The air-alkaline battery works pretty much the same way.

Why do lithium coin cells last so long?

Lithium batteries last a very long - up to ten years - even when they are hardly used at all. The self-discharge per year is only 1% of the capacity.

What is the specific feature of alkaline coin cells?

They can deliver high currents as the initial voltage level is 1.5 Volts. However, after a while, the voltage drops relatively fast. That is why these batteries are less suitable and reliable for cameras and measuring equipment.

Why is there always silver oxide in the batteries for watches?

The voltage of this system is high and remains constant for quite a long time. The time must always be reliable.

What kind of coin cell batteries are there?

There are several systems. The properties are tailored to the most important applications.

Silver oxide (watches, cameras): High constant voltage, self-discharge less than 5% per year.

Alkaline (electrical appliances): Supplies large currents, voltage drops during use, self-discharge less than 3% per year.

Lithium (cameras and electronic devices): Self-discharge less than 1% per year, not suitable for heavy loads.

Zinc air (hearing aids): High capacity, self-discharge 3% per year (if not activated).

Mercury oxide (electrical appliances, hearing aids and cameras): Supplies large currents, self-discharge 2% per year, environmentally unfriendly 15% mercury.

Mercury-containing batteries have not been manufactured since 1998 and have not been supplied by factories since 1999. A replacement zinc air battery is available for a small number of these batteries.

What is a coin cell battery used for?

There are many applications. The most important are watches, cameras and hearing aids. In addition, calculators, games and car alarms are major consumers.

What is a coin cell or button battery?

A button cell is a round battery whose diameter is usually greater than its height. Sometimes they are extremely small and then they look like a button or a coin. That is why they are also called button cells.

What does disposal fee mean?

For all products that contain a battery (or are loose), a disposal fee must be paid to Stibat. This is in line with international laws and regulations (environment). This also applies to devices that are supplied with batteries (e.g. torches).
Commercially used batteries can be collected by a licensed collection company. Commercially used batteries can be collected by a licensed collection company.

What is the Stibat?

Stibat stands for Batteries Foundation. This is the organisation that coordinates the collection activities for empty batteries in the Netherlands. They develop activities in various areas to inform everyone about the how and why of the collection of used batteries. And this is done on a non-profit basis. Since 1995 there has been a legal regulation stating that used batteries must be collected and recycled by or on behalf of producers and importers of batteries. Stibat has taken over this task. A so-called disposal fee must be paid per battery. Elfa is a member of Stibat and charges you the relevant disposal contribution for each battery.


Stibat arranges the collection of batteries. Empty batteries do not belong in the bin. It may contain substances that are harmful to the environment, such as the heavy metals mercury, lead and cadmium. They harm the environment when disposed in the household waste. That’s why it is a good thing that more people return empty batteries. Separate from other waste. Not only the well-known penlite batteries can be returned, but also coin cells and the batteries in, for example, mobile telephones, photo and film cameras and cordless tools. Rechargeable batteries may last longer than single-use batteries, but at some point they also cease to function properly and must be disposed of responsibly. Handing in empty batteries separately not only saves the environment, but the metals of the battery are recycled for reuse (think nickel, steel and zinc). New products are made from this, such as zinc gutters, crash barriers, but also new batteries. From 25 million kilos of recycled batteries, 13 million kilos of usable metals were recovered over a period of 12 years! That is a significant saving on our mineral resources.


Click here for more information.

What is NEN?

NEN stands for National Standardisation Institute. Those who participate in standardization share their knowledge in order to benefit from it together with others. Standardisation strives for efficient, safe, healthy and sustainable products and processes. Several interests are united in a smart way. NEN is the national standardization institute in the Netherlands. They work on economic growth and well-being in a European (CEN, CENELEC and ETSI) and worldwide (ISO, IEC and ITU) context. As the Dutch centre of standardization, NEN helps companies and other organisations to make clear and applicable agreements with each other.


Click here for the website of NEN.

Does Elfa have a RoHS declaration?

Yes. In this declaration, Elfa confirms that its assembly workshop is RoHS compliant. For the sake of completeness, we state here that the RoHS guidelines do not apply to batteries.

What is RoHS?

RoHS stands for Restriction of the use of certain Hazardous Substances. In February 2003, the European RoHS directive came into existence. It concerns the use of lead, cadmium, mercury, hexavalent chromium, PBB and PBDE. Lead-free soldering is an important part of this guideline. For the complete EU guideline, please click here.

How long does Elfa exist?

Elfa has been around for over 100 years. Click herefor more information on Elfa’s history.

What are Elfa’s company details such as VAT number and KVK number?

Elfa Elementenfabriek B.V.
Madridstraat 5 – 7
1175 RK Amsterdam (Lijnden)
BTW: NL800906305B01
KVK: 33068133

Bank IBAN EUR: NL40INGB0007235888
Bank IBAN USD: NL65INGB0020030126
Bank IBAN GBP (UK) GB74BUKB20490843454959
Swift / BIC: BUKBGB22

How do you recognise formats of primary batteries?

Formats are given a name and can also have a code. The names are more or less the same in all countries, although other terms are often used in common parlance. The codes are different everywhere, e.g. the international IEC code and the American code. Also each brand often uses its own codes. It is therefore often difficult to recognize the codes on packaging. The IEC code is the most common. The battery types are identified by the letters in the IEC code. Alkaline, for example, is called LR.


IEC-code VS-code Name Popularly Dimensions (mm) (diam x height)*
LR3 AAA Micro Pencil 10,5×44,5
LR6 AA Mignon Penlite 14,5×50,5
LR14 C Baby English bar 26,2×50
LR20 D Mono Large rod, mono 34,5×61,5
6LR61 E 9 Volt E-block 26,5×17,5×48
3LR12 Normal 4,5Volt 26x22x67


* there can sometimes be some tolerance differences in this.

What exactly does mAh mean?

The capacity and lifetime of a battery depends on its current, expressed in thousandths of Amps, or milli-Amps (mA) multiplied by the number of hours (the h of "hours") it can provide power.

What does internal resistance mean for a battery?

Certain (chemical) systems can handle energy flows more easily than other systems. In addition to the voltage (volts), the internal resistance (Ohms) of the battery is also important. Battery types with low internal resistance are Nickel Cadmium, Nickel Hydride, Alkaline, Lithium Photo and Mercury Oxide respectively. Lithium, zinc air, silver oxide and zinc carbon have a higher internal resistance

How does a battery work?

A battery is a cell that can give off electrical energy through internal chemical reactions. The cell consists of a plus and a minus pole that are separated by a layer of electrolyte. The negative pole is brought into contact with the positive pole through the device in which the battery is placed and thereby emits electricity.

Does the amount of capacity determine the lifetime?

Yes. The higher the capacity, the longer the battery life. The capacity is expressed in Ampere hours (Ah) or milli-Ampere hours. (mAh). You can usually read how high the capacity of the battery is on the battery itself and on the packaging. For the application equipment, more capacity means more operating time. It is therefore not harmful to use stronger batteries, but it is harmful to use voltages other than those indicated.

What are NiMH batteries?

NiMH-batteries (Nickel Metal Hydride batteries) are a type of rechargeable battery that is widely used in different kinds of electronic devices. They are an improved version of the NiCd-batteries (Nickel Cadmium batteries), because they contain fewer heavy metals, making them more environmentally friendly. They also can store more energy and are less susceptible to a memory effect. This makes them very easy to maintain.

How to revive a NiMH battery

It can be possible in some instances to revive an old NiMH-battery at your own risk, but the success rate may vary depending on the current condition of the battery. If there is any physical damage like corrosion, bulging or leaks, it may not be safe to revive it.


Sometimes charging the battery can help. When the NiMH battery has been discharged for a long time and is completely empty, it might enter a deep discharge state. In some cases, cycling the battery might be the answer, by fully charging and discharging several times.


Some NiMH battery chargers, also known as a smart charger, come with a reconditioning or trickle charge feature. This applies a low current to the battery for a longer period, which can revive batteries that have been deeply discharged.


An empty NiMH-battery will have a low voltage. You can verify this by using a voltmeter. If the battery has 0V, it cannot be charged in a with a smart charger.


However, a NiMH-battery can be revived by using cables and another fully charged one. Connect one of the cables from positive of the fully charged battery to the positive of the empty battery. Keep them connected for three seconds and then disconnect them.


With the voltmeter you can see if the empty battery has now some voltage in it. Now you can put it in a smart charger again and it will start charging.

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