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    Information about batteries and charging systems

    To ensure that you don’t start a development discussion unaware, here is a summary of the most important points concerning mobile energy solutions!

    Cell structure and functioning of a rechargeable battery

    The essential components of a battery 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

    Rechargeable 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

    An assembled 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), because this is the decisive interface between the battery and the external communication. It also enables the software to be adapted to the corresponding safety measures and ensures safe operation of the battery system.

    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 equalised again with the help of a charger by charging the nominal voltage of the system to the maximum nominal voltage that the battery can reach.
    The voltage equalisation takes place through 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 that can store the charge.
    The current strength determines the capacity as a function of time.
    As a result, battery packs that have a higher capacity have longer or shorter charging times, depending on the amperage.
    In order to achieve a longer service life, we charge the batteries through the charging cycles with the gentlest possible charging current (0.2% of the charging capacity).

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

    Handling Li-Ion cells

    There are a number of things to consider when handling Li-Ion cells correctly. That is why we have put together a few tips for you 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 due to the high energy density, irrereparable consequences could arise in the battery system, causing high temperatures to develop and ultimately a potential for fire.
    • Deep discharge: Both deep discharge and overcharge can damage the chemical system of a battery cell. A deep discharge of a single cell voltage below 2.5V, for example, can lead to a polarity reversal of the poles and can also damage the separator. This would cause a short-circuit of the electrodes, which in turn would increase the temperatures and ultimately trigger a fire.
    • Overcharging: If a system is overcharged, the resulting heat can trigger a thermal reaction inside the battery. This reaction is also known as a “thermal runaway” and causes the cell to “blow”. It then shows an increased chemical reaction and toxic gases are produced. If the system continues to be overcharged, a self-reinforcing heat build-up occurs within the battery, which can lead to the core of the battery melting. The result is a fire or even an explosion of the cells. That 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, but extreme 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 area of application.

    Frequently asked questions


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

    Li-ion = Lithium-Ionen
    NiCd = Nickel-Cadmium
    LiPo = Lithium-Polymer
    LiFePO4 = Lithium-Eisen-Phos­phat
    LiMn = Lithium-Mangan
    NiMH = Nickel-Metall­hy­drid-Akku­mu­lator
    LTO bzw. Li4Ti5O12 = Lithium-Titanat-Oxid
    Li-SOCI2 = Lithium-Thionyl-Chlorid

    What do the abbreviations SoC, Ah, mAh, Wh, V, A, PCM mean?

    SoC = State of Charge (Lade­zu­stand)
    Ah = Ampere­stunden
    mAh = Milli­am­pe­re­stunden
    Wh = Watt­stunden
    = Volt (Span­nung)
    = Ampere
    PCM = Protec­tion Circuit Module (Schut­z­elek­tronik)

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

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

    The number stands for the number.

    6S1P = Thus 6 cells in series and 1 cell in parallel.
    7S10P = Thus 7 cells in series and 10 cells in parallel.

    What is the difference between a rechargeable battery and a battery?

    A battery is rechargeable.

    What is the difference between a primary and secondary cell?

    Primary cell is not rechargeable (battery).
    Secondary cell is rechargeable (battery).

    What is a cylindrical cell or round cell?

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

    Can I still buy NiCd (nickel-cadmium) batteries?

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

    How long do I have a guarantee on batteries and rechargeable batteries?

    The guarantee period for batteries and rechargeable batteries is 6 months.

    Can I have my battery tested for its current condition?

    Yes, but laboratory measuring equipment is necessary for this.

    When should you always replace batteries?

    If the battery for the actual application (e.g. e-bike, golf trolley) can no longer supply sufficient energy to ensure sensible operation.
    However, one should always remember the environmental aspect here. Disposing of rechargeable batteries is relatively costly for the sake of the environment.
    Before disposing of them, everyone should therefore consider whether it is really necessary.

    However, there are also other reasons that should lead to immediate but proper disposal.
    For example, it can be dangerous if the battery has been mechanically damaged, e.g. if it has been dropped.
    It is also advisable to have the battery checked if it becomes noticeably warm during operation. You can have this done by a specialist battery company.
    Lithium-polymer batteries can also become swollen. 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 quickly as possible.

    Where can I dispose of batteries and rechargeable batteries?

    It is best to dispose of your rechargeable batteries at your specialist dealer or at the responsible hazardous waste collection points.
    If you want to dispose of individual cells, there are already many markets that offer battery collection boxes for disposal.

    As a large number of batteries are collected in the collection boxes, it is safer to tape off the terminals before disposal to avoid the danger of a possible short circuit.

    More detailed information on the correct disposal can be found in the following document:
    AUVA leaflet on handling lithium-ion batteries.

    What is a charging cycle?

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

    What is nominal 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 3.6 volts. The nominal voltage of a rechargeable 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 does the protection electronics control?

    In general, everyone should take care that their battery is not used 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.
    Should an unfavourable situation nevertheless occur for the battery, the protection electronics will ensure that the battery interrupts operation and thus a possible dangerous situation is avoided. These include circumstances such as:

      • Protection against overcharging
      • Protection against discharge into the deep discharge range
      • Protection against excessive currents (e.g. in the event of a short circuit)
      • Dispose of protection against too high temperatures


    What is deep discharge of a rechargeable battery?

    Deep discharge of an accumulator means the state after current drain until the capacity is almost completely exhausted. or below a certain voltage.

    What does self-discharge mean?

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

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

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

    What does PEMS mean?

    Die Abkürzung PEMS steht für Portable Emission Measurement System, oder auf Deutsch mobiles Emissionsmessgerät.
    Dabei handelt es sich um ein mobiles Gerät zur Messung von Abgasemissionen eines Kraftfahrzeugs während einer realen Straßenfahrt.

    What is the memory effect?

    The memory effect: If NiCd batteries are not fully discharged before recharging, 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.

    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 method 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 uses the CCCV charging method for Li-ion batteries.

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

    The IQ338, IQ338XL and IQ328+ AccuPower IQ chargers show “zero” 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, this is more of an ignition than an explosion, and for this to happen, something must have gone wrong during handling.
    In general, it is important to ensure that a suitable charger is used specifically 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 whether it is equipped with protection electronics (usually called PCM) with integrated balancing. These electronics monitor the battery and protect it from all inadmissible events. If one of these events occurs, the battery switches off and goes into self-protection, which you can reset yourself in most cases. If you follow these points, you are safe on the road with Li-Ion technology and can use the enormous power of these batteries without danger.

    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.
    Spare batteries may only be stowed in hand baggage and must be packed individually and protected so that short circuits are excluded.
    Only batteries for personal use may be carried.

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

    No, only with a suitable lithium-ion charger.
    In general, it is important to always use a suitable charger specifically 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 whether it is equipped with protection electronics (usually called PCM) with integrated balancing. These electronics monitor the battery and protect it from all inadmissible events. If one of these events occurs, the battery switches off and goes into self-protection, which you can reset yourself in most cases. If you follow these points, you are safe on the road with Li-Ion technology and can use the enormous power of these batteries without danger.

    May 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.

    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 it is possible to exchange individual cells.

    Can I charge my e-bike battery overnight?

    No, because batteries must not be charged unattended.

    Hazardous goods transport and certifications

    Where can I find the transport information for the battery?

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

    What is the Material Safety Data Sheet (MSDS)?

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

    What is a safety data sheet for?

    Safety data sheets, also called material safety data sheets, are used to communicate safety-related information on substances and mixtures.

    What does dangerous goods mean?

    Articles or substances which are capable of presenting 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 use, e.g.: Battery housing, battery terminals, marking and protection devices.

    Lithium cells:
    A single cell lithium battery is considered a “cell” and shall be tested in accordance with the testing 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.

    What means UN3480?

    UN3480 is the UN number for lithium ion batteries.

    Is NiMH (nickel metal hydride) dangerous goods?

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

    What is ISO9001?

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

    Was ist die ISO14001?

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

    What is CE-Zertifikat?

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

    What is a UN-Number?

    The UN number is a four-digit number used toidentify substances or articles in accordance with the UN Recommendations for the carriage of dangerous goods. Each dangerous good is assigned a UN number in the dangerous goods lists of the regulations of all modes of transport.

    What means UN3480?

    UN3480 ist die UN-Nummer für Lithium-Ionen-Batterien.

    What means UN3481?

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

    What means UN3090?

    UN3090 is the UN number for Lithium metal batteries.

    What means UN3091?

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

    What means UN3496?

    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 all transport carriers basically check 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 shall provide the test summary set out in the UN Manual of Tests and Criteria Part III, subsection 38.3, paragraph 38.3.5.

    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 means IEC?

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

    What means ADR?

    ADR stands for “Accord européen relatif au transport international des marchandises dangereuses par route”. In German, it means “European Agreement concerning the International Carriage of Dangerous Goods by Road”.

    Was bedeutet IMDG?

    The IMDG Code (International Maritime Code for dangerous Goods) is the transport regulation for dangerous goods in maritime transport.

    What means ICAO?

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

    Was bedeutet IATA?

    The International Air Transport Association was founded in Cuba as an umbrella organisation for the airline industry.

    What means ADN?

    The European Agreement concerning the International Carriage of Dangerous Goods by Inland Waterways (abbreviation ADN, from Accord européen relatif au transport international des marchandises dangereuses par voie de navigation intérieure).

    What means DGD?

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

    What means DGR?

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

    What means IMO?

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

    What is an IMO-Erklärung?

    An IMO declaration is thetransport document for the transport of dangerous goods by sea (English: IMO declaration).

    What means IP?

    IP = International Protection.
    Describes aclass of protection which indicates the suitability of electrical equipment for various environmental conditions, in addition to the protection of people against potential hazards when using it. 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 a space in between). These indicate the extent of protection an enclosure offers with regard to contact or foreign bodies (first code number) and moisture or water (second code number).

    Whats are Incoterms?

    These areinternational commercial terms. International Commercial Terms.

    What means REACH?

    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 means RoHs?

    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 placing on the market of hazardous substances in electrical equipment and electronic components.

    What is a Dual-Use Explanation?

    Dual-use describes the principle usability of goods for civilian as well as military purposes. This includes in particular goods from the field of sensitive electronics, telecommunications, IT technology, but also data processing programmes or other technologies.

    What is a long term declaration?

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

    What is a declaration of origin / supplier's declaration?

    A supplier’s declaration is a proof of the preferential origin of an imported good. It is required by the exporter as proof for issuing and applying for a preference document.

    What is a customs tariff number?

    Companies need a customs tariff number, also called a commodity code, to process 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 the goods in the customs tariff of the European Union.

    What is the net weight?

    This is the weight of e.g. a battery without packaging.

    What is the gross weight?

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