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Knowledge transfer

So that you do not start a development discussion unknowingly, the most important points concerning mobile energy solutions are summarized here!

Services & Competencies

When assembling our battery packs, we go through an extensive quality assurance process to achieve a higher safety standard.
Development of special solutions

Research & Development

Our main area of activity is first and foremost research and then the development of new marketable products.
Research & Development

Knowledge transfer

Since knowledge only comes from processed information, we have collected all kinds of information on the subject of batteries on our knowledge transfer page.
Knowledge transfer

Information about batteries and charging systems

Cell structure and function of a battery

The essential components of a rechargeable cell are its two electrodes and an electrolyte.

The electrodes are called cathode and anode and are separated both spatially and electrically by a separator.

It is very important that the separator is permeable to the ions so that the electrochemical reaction within the cell can take place properly.

Battery packs

Batteries can be operated by different systems:

Ni-MH = nickel metal hydride
Li-Ion = Lithium Ion
LiFePo4 = lithium iron phosphate accumulator
Li-Po = Lithium Polymer

A ready-made battery pack consists of several arrangements of individual cells.
The exact arrangement of the cells depends on the desired voltage and capacity.

The higher the number of cells, the higher the energy density of the interconnected cell system (especially in a Li-Ion system).
It is essential that the cell system is coupled with a battery management system (= protection electronics), as this is the decisive interface between the battery and external communication. It also allows the software to be adapted to the appropriate safety measures and ensures that the battery system is operated safely.

Charging characteristics

Charging means that a voltage equalisation takes place between two systems.

If a battery system is discharged, its nominal voltage also drops.

This can be compensated for with a charger by recharging the nominal voltage of the system to the maximum nominal voltage that the battery can reach.

Voltage equalisation is achieved by the so-called charge transport (= current flow) when the voltage potential of the charger is higher than that of the respective consumer.

In this case a battery is the consumer which can store the charge.

The current strength determines the capacity as a function of time.

Consequently, battery packs with a higher capacity have longer or shorter charging times depending on the current intensity.

In order to achieve a longer service life, we charge the batteries through the charging cycles with a charging current that is as gentle as possible (0.2% of the charging capacity).

We offer intelligent rapid charging systems for battery systems and single cells, which are developed in-house by us.

Handling of Li-Ion cells

There are a few things to consider when handling Li-Ion cells correctly. We have therefore put together some tips for you here to help prevent accidents caused by damaged batteries:

  • Short-circuit: One of the introductory and at the same time most important rules for Li-Ion systems is that a short-circuit should be avoided at all costs, as the high energy density could have irreparable consequences in the battery system, causing high temperatures to develop and finally a fire potential to arise.
  • Deep discharge: Both deep discharge and overcharging can damage the chemical system of a battery cell. For example, a deep discharge of a single cell voltage below 2.5V can cause the polarity of the poles to be reversed and also damage the separator. This would lead to a short circuit of the electrodes, which in turn would cause the temperatures to rise and finally cause a fire.
  • Overcharging: If a system is overcharged, the heat generated can trigger a thermal reaction inside the battery. This reaction is also known as a "thermal runaway" and causes the cell to "run through". It then shows an increased chemical reaction and toxic gases are produced. If the system continues to overcharge, heat is generated inside the battery, which is self-amplifying and can cause the core of the battery to melt. The result is a fire or even the explosion of the cells. This is why modern cells have a pressure relief valve in their design to prevent an explosion. If this valve is triggered, toxic gases and the liquid electrolyte can escape from the cell, although the utmost caution is required here!

Our battery systems are protected by our self-developed and installed Battery Management Systems (= BMS), which are individually adapted to the respective application.


Frequently asked questions


What do the abbreviations mean: Li-ion, NiCd, LiPo, LiFePO4, LiMn, NiMH, LTO or Li4Ti5O12, Li-SOCI2?

Li-ion = lithium-ion
NiCd = Nickel-Cadmium
LiPo = lithium polymer
LiFePO4 = Lithium Iron Phosphate
LiMn = lithium manganese
NiMH = nickel-metal hydride accumulator
LTO or Li4Ti5O12 = lithium titanate oxide
Li-SOCI2 = lithium thionyl chloride

What does the abbreviation SoC, Ah, mAh, Wh, V, A, PCM mean?

SoC = State of Charge
Ah = ampere hours
mAh = milliampere-hours
Wh = watt-hours
V = Volt (voltage)
A = Ampere
PCM = Protection Circuit Module (protection electronics)

What do the different designations 6S1P, 7S10P etc. mean?

The designations stand for the arrangement of the cells
S = Serial
P = Parallel

The number stands for the number.

6S1P = Thus 6 cells serial and 1 cell parallel.
7S10P = So 7 cells serial and 10 cells parallel.


Serial = Double (or multiple) voltage, but single capacity of the cells.
Parallel = single voltage, but double (or multiple) capacity of the cells

What is the difference between accumulator and battery?

A accumulator is rechargeable.
A battery is not rechargeable.

What is the difference between a "primary" and "secondary" cell?

Primary cell is not rechargeable.
Secondary cell is rechargeable.

What is a cylindrical cell or round cell?

Cylindrical cells are particularly robust and for this reason are used in many applications. They consist of a cylindrically wound cell with a hard case.

Can I still buy NiCd (Nickel-Cadmium) batteries?

From 2017, NiCd batteries may only be used in emergency systems, emergency lighting and medical equipment. Only stocks already in the EU may be sold off. NiCd batteries can be replaced by identical NiMh (nickel-metal hydride) batteries with the same values. Old chargers can still be used for NiMh batteries.

How long do I have warranty on batteries and accumulators?

The warranty period for batteries and accumulators is 6 months.

Can I have my battery tested for its current condition?

Yes, but this requires laboratory measuring equipment.

When should batteries always be replaced?

If the battery for the actual application (e.g. e-bike, golf trolley) can no longer provide sufficient power to ensure proper operation.
However, in this case you should always remember the environmental apse. Disposal of batteries is relatively costly for the sake of the environment.
Everyone should therefore consider before disposal whether it is really necessary.

But there are also other reasons which should lead to an immediate but appropriate disposal.
For example, it can be dangerous if the battery has been mechanically damaged, e.g. if it has been dropped.
Even if the battery becomes noticeably warm during operation, it is advisable to have it checked. You can have this done by a company specialising in batteries.
Lithium-polymer batteries may also inflate. Cells in this state are often subject to very high pressure, which can be very dangerous.
These batteries should also be disposed of properly as soon as possible.

Where can I dispose of batteries and accumulators?

The best way to dispose of your batteries is to take them to your specialist dealer or the appropriate collection point for problematic materials.
If it is single cells that you wish to dispose of, there are already many markets nowadays that offer battery collection boxes for disposal.

After a large number of batteries have been collected in the battery collection boxes, it is safer to tape off the poles before disposal to avoid the danger of a possible short circuit.

What is a charge cycle?

A charge cycle describes the charging of a battery from the lowest state of charge up to 100%.

What is rated voltage?

The voltage of an electrical device or voltage circuit in normal operation. This value is usually specified by the manufacturer, a lithium ion cell for example has a nominal voltage of about 3.6Volt. The nominal voltage of a battery can be found in the technical data sheet.

What is operating voltage?

The voltage required to operate an electrical circuit and thus a device.

What controls the protection electronics?

In general, everyone should make sure that their battery is not operated improperly or exposed to unfavourable or even dangerous conditions.
How to handle the battery correctly is described in detail in the enclosed information sheet or you can also find the necessary information on the homepage.
If an unfavourable situation should nevertheless arise for the battery, the protective electronics ensure that the battery interrupts operation, thus avoiding a potentially dangerous situation. These include circumstances such as:

  • Protection against overcharge
  • Protection against discharge into the deep discharge area
  • Protection against excessive currents (e.g. in case of short circuit)
  • Dispose of protection against too high temperatures.
What is deep discharge of a battery?

Deep discharge of an accumulator is understood to be the state after current withdrawal until the capacity is almost completely exhausted or until it falls below a certain voltage.

What does self-discharge mean?

Self-discharge refers to processes that occur automatically and lead to batteries and accumulators discharging more or less quickly, even when no electrical consumer is connected.

Should I remove the battery from my device when not in use?

Yes, because a small current could flow even when the device is switched off, which leads to a deep discharge after a longer period of time.

What is the memory effect?

The memory effect: if NiCd batteries are not fully discharged before charging, this point becomes their full operating capacity. The battery "remembers" how far it has been discharged and can no longer be used afterwards. To a lesser extent, the same memory effect occurs with NiMH batteries. This is caused by a change in the crystals on the electrodes in the battery.

What does PEMS mean?

The abbreviation PEMS stands for Portable Emission Measurement System.

This is a mobile device for measuring exhaust emissions of a motor vehicle during a real road journey.

AccuPower IQ-Chargers

Which charging method is used by the AccuPower IQ203/IQ338/IQ338XL/IQ328+/IQ216 to detect a full battery or to stop charging?

The AccuPower IQ chargers use two different charging methods. Which one is selected depends on which battery is inserted into the charger.

While the -dV/dt charging method is used for NiCd and NiMH batteries, the charger works with the CCCV charging method for Li-Ion batteries.

What does it mean when the display of my AccuPower IQ338/IQ338XL/IQ328+ shows "null"?

The IQ338, IQ338XL and IQ328+ AccuPower IQ chargers show "null" on the display when no battery cell is inserted in the charger.

Handling of lithium-ion batteries

Can lithium-ion batteries explode?

Yes, they can. However, they are more likely to ignite than explode, and for that to happen, something must have gone wrong with the handling.
In general, you should always ensure that a suitable charger is used, especially for Li-Ion batteries. This charger should also meet a certain quality standard, so please do not buy batteries and chargers from unknown sources. When buying your battery, ask if it is equipped with protective electronics (usually also called PCM) with integrated balancing. These electronics monitor the battery and protect it from all unacceptable events. Should one of these events occur, the battery switches off and goes into self-protection, which you can reset yourself in most cases. If you follow these points you will be safe on the road with the Li-Ion technology and can use the enormous power of these batteries without any danger.

Can I charge my lithium-ion batteries with any charger?

No, only with a suitable lithium-ion charger.
In general it is important to ensure that a suitable charger especially for Li-Ion batteries is always used. This charger should also meet a certain quality standard, so please do not buy batteries and chargers from unknown sources. When buying your battery, ask if it is equipped with protective electronics (usually also called PCM) with integrated balancing. These electronics monitor the battery and protect it from all unacceptable events. Should one of these events occur, the battery switches off and goes into self-protection, which you can reset yourself in most cases. If you follow these points you will be safe on the road with the Li-Ion technology and can use the enormous power of these batteries without any danger.

Can I ship a lithium battery?

In principle yes, if you have the appropriate training or instruction for dangerous goods.
This is the only way to ensure that you are familiar with the regulations.

Can I take my lithium-ion battery with me on the plane?

Yes, in hand luggage and checked baggage, if the Wh = watt-hour capacity does not exceed 100Wh.
Replacement batteries may only be stowed in hand luggage and must be packed individually and protected so that short circuits are impossible.
Only batteries for personal use may be carried.

Handling and maintenance of e-bike batteries

Can an e-bike battery or lawnmower battery be repaired or replaced?

In principle, yes. Only after checking the battery can it be determined whether individual cells can be replaced.

Can I charge my e-bike battery overnight?

No, because batteries must not be charged unattended.

Transport of dangerous goods and certification

Where can I find the transport information for the battery?

In SDB / MSDS (Material Safety Datasheet) at point 14.

What is the Material Safety Data Sheet (MSDS) or Safety Data Sheet (SDS)?

The Material Safety Data Sheet is required for the transport of dangerous goods.
The certificate is part of the UN38.3 test.

Why a safety data sheet?

Safety data sheets, also known as material safety data sheets, are used to transmit safety-related information on substances and mixtures.

What does dangerous goods / hazardous goods mean?

Articles or substances which are capable of posing a risk to health, safety, property or the environment. e.g: UN3480 lithium-ion batteries.

What are cells and what are batteries when transporting dangerous goods?

Lithium batteries (battery = battery pack):
"Battery" means two or more cells which are electrically connected and equipped with devices necessary for its use, e.g: battery cases, battery terminals, marking and protection devices.

Lithium cells:
A single cell lithium battery is considered a "cell" and must be tested in accordance with the test requirements for a "cell" for the purposes of these Regulations and the requirements of subsection 38.3 of the UN Manual of Tests and Criteria.

Is NiMH (nickel-metal hydride) a hazardous material?

Yes, but only in sea freight (IMDG).
In air freight there is an exception A199 (special regulation).
On road / rail it is not subject to the dangerous goods regulations, therefore on road and rail no dangerous goods.

What is ISO9001?

ISO9001 is an international quality management standard. It describes the requirements that the management system of an organisation - whether it is a company or a public authority - must meet in order to comply with a certain standard in the implementation of quality management

What is ISO14001?

The international environmental management standard ISO 14001 defines globally recognised requirements for an environmental management system and is part of a family of standards.

What is a UN-number?

The UN-number is a four-digit number used to identify substances or objects in accordance with the UN Recommendations on the Transport of Dangerous Goods. A UN number is assigned to each dangerous goods in the dangerous goods lists of the regulations of all modes of transport.

What does UN3480 mean?

UN3480 is the UN number for lithium ion batteries.

What does UN3481 mean?

UN3481 is the UN number for lithium ion batteries packed or lithium ion batteries in equipment.

What does UN3090 mean?

UN3090 is the UN number for lithium metal batteries.

What does UN3091 mean?

UN3091 is the UN number for lithium metal batteries packed or lithium metal batteries in equipment.

What does UN3496 mean?

UN3496 is the UN number for nickel metal hydride batteries.

What is the UN38.3 test?

The UN38.3 test is a transport and safety test for lithium batteries and cells.
Basically all lithium cells and battery packs must be tested according to UN Manual 38.3 UN. In the course of this UN test you will also receive the MSDS / SDB (Material Safety Datasheet), which checks all carriers in advance whether they accept these goods for transport. 

What is a UN test summary according to 38.3?

Manufacturers and subsequent distributors of cells or batteries manufactured after 30 June 2003 must provide the test summary as specified in the UN Manual of Tests and Criteria Part III, subsection 38.3, paragraph 38.3.5.

What is the CE certificate?

The CE certificate (declaration of conformity) confirms that the manufacturer meets the requirements of EU regulation 765/208 for the product.

What is the IEC62133 test?

IEC 62133 is one of the most important safety standards for rechargeable lithium-ion batteries used in consumer products, IT equipment, tools, laboratory, household and medical equipment.

What does IEC mean?

International Electronical Commission; international standardisation body under private law for standardisation in the field of electrical engineering and electronics; based in Geneva.

What does ADR mean?

ADR stands for "Accord européen relatif au transport international des marchandises dangereuses par route". In English this means: "European Agreement concerning the international carriage of dangerous goods by road".

What does IMDG mean?

The IMDG Code (International Maritime Code for Dangerous Goods) is the transport regulation for dangerous goods by sea.

What does ICAO mean?

The International Civil Aviation Organization is a specialized agency of the United Nations with headquarters in Montreal, Canada.

What does IATA mean?

The International Air Transport Association was founded as the umbrella organisation of the airline in Cuba.

What does ADN mean?

The European Agreement concerning the international carriage of dangerous goods by inland waterways (ADN, from Accord européen relatif au transport international des marchandises dangereuses par voie de navigation intérieure).

Was bedeutet DGD?

Dangerous goods declaration, is the shipper's declaration for the shipment of dangerous goods by air.

Was bedeutet DGR?

Dangerous Goods Regulations (DGR) (IATA Dangerous Goods Regulations) is a set of rules for the transport of dangerous goods by air of IATA.

What does IMO mean?

International Marine Organisation, i.e. International Maritime Organisation based in London.

What is an IMO Declaration?

An IMO declaration is the transport document for the transport of dangerous goods by sea.

What are Incoterms?

These are international trade rules. International Commercial Terms.

What does REACH mean?

Regulation (EC) No 1907/2006 is an EU chemicals regulation that came into force on 1 June 2007. REACH stands for Registration, Evaluation, Authorisation and Restriction of Chemicals.

What does RoHs mean?

The EU Directive 2011/65/EU serves to restrict the use of certain hazardous substances in electrical and electronic equipment. It regulates the use and marketing of hazardous substances in electrical appliances and electronic components.

What is a dual-use declaration?

Dual-use describes the basic usability of goods for both civil and military purposes. This includes in particular goods from the field of sensitive electronics, telecommunications, IT technology, but also data processing programs or other technologies.

What is a long-term supplier's declaration?

The supplier's declaration is a document that can normally only be used in the European Union. It serves as proof when applying for or issuing a preference certificate. It can also be used to apply for a certificate of origin (e.g. EUR. 1).

What is an origin declaration / supplier declaration?

A supplier's declaration is a proof of the preferential origin of imported goods. It is required by the exporter as proof for issuing and requesting a preferential proof.

What is a customs tariff number?

Companies need a customs tariff number, also known as a commodity code, to conduct their foreign trade transactions. The customs tariff number is the numerical coding of a good. The determination of the customs tariff number is called tariff classification or classification of goods in the customs tariff of the European Union.

What is the net weight?

This is the weight of a battery without packaging, for example.

What is the gross weight?

This is the weight e.g. of a battery with packaging.

What does IP mean?

IP = International Protection
Describes a type of protection that indicates the suitability of electrical equipment for various environmental conditions, and also the protection of people against potential hazards during use. Protection classes are IP00 to IP69K.

The letters IP, which are always present in the protection class designation, are followed by two code numbers (generally without spaces). These indicate the degree of protection provided by an enclosure against contact or foreign bodies (first digit) and moisture or water (second digit).