archive-nl.com » NL » H » HEFRA.NL

Total: 362

Choose link from "Titles, links and description words view":

Or switch to "Titles and links view".
  • Hefra - Technical info - Explosie
    can cause a full short circuit When reaching full state of charge any lead acid battery will produce explosive oxyhydrogen gas dissipating from the battery vents Under those conditions any spark can cause an explosion that not only will damage the battery but also disperse acid into the surroundings Anyone close to the battery may be injured Most battery explosions take place at the moment of connecting and disconnecting cables

    Original URL path: http://www.hefra.nl/docs/webshop.asp?act=doc&id=4782 (2016-05-01)
    Open archived version from archive


  • Hefra - Technical info - Gridcorrosie
    Grid corrosion The electrolyte inside a battery is not only in contact with the active mass at the plate but also with the uncovered parts of the grid itself Grid corrosion is a normal phenomenon in a battery where the lead of the positive grid is converted into lead dioxide As a result of this conversion the electrical conductivity and mechanical strength of the gradually decline until the plates collapse

    Original URL path: http://www.hefra.nl/docs/webshop.asp?act=doc&id=4784 (2016-05-01)
    Open archived version from archive

  • Hefra - Technical info - Verlies van Actieve Massa
    into lead oxide during discharge the lead oxide is converted back into lead sulphate Because lead sulphate has a larger molar volume than lead the active material will shrink and swell with each cycle weakening and shedding the active material and ultimately leading to loss of plate capacity Accelerated loss of active material also known as a PCL or Premature Capacity Loss can be caused by deep discharge Typical examples

    Original URL path: http://www.hefra.nl/docs/webshop.asp?act=doc&id=4786 (2016-05-01)
    Open archived version from archive

  • Hefra - Technical info - Terminal corrosion
    corrosion Galvanic corrosion is caused by the potential difference between metals that come into contact with each other in this case the material of the terminal and the connector Corrosion generally comes as white lead or zinc crystals or if the connections are made of aluminium as aluminium sulphate Bronze connectors will typically corrode with blue crystals Very often the corrosion shows a combination of white and blue crystals white because of the lead in the connector clip and blue by the purchaser in the cable This type of corrosion can be prevented by applying a terminal spray or vaseline If the corrosion has already set in the terminals and connectors have to be cleaned first Check for damage a smooth sleek surface is important for a good electrical conductivity 2 Electrolytic corrosion If the battery contains too much electrolyte because it has been topped up above the maximum level or in discharged condition causing the battery s acid to overflow and come into contact with the terminals and connectors and thus resulting in corrosion This problem can be prevented by proper battery care Lesser known is that the electrolyte may also find its way to the outside through the

    Original URL path: http://www.hefra.nl/docs/webshop.asp?act=doc&id=4788 (2016-05-01)
    Open archived version from archive

  • Hefra - Technical info - Sulfation
    finely divided amorphous form of lead sulphate is produced During charging the amorphous lead sulphate is easily converted back to lead lead dioxide and sulfuric acid in essence returning the battery to its former state If a battery is not fully recharged soon after a deep discharge the lead sulphate will crystallize These large crystals clog the pores of the active mass and cover the plate surface so that charging

    Original URL path: http://www.hefra.nl/docs/webshop.asp?act=doc&id=4790 (2016-05-01)
    Open archived version from archive

  • Hefra - Technical info - Stratificaton
    on the bottom causing the upper half of the cell to be acid poor The upper part of the battery plate will sulfate because of depleted electrolyte and the lower section will succumb to mass loss and grid corrosion due to overcharge Stratification occurs if a battery is kept at a state of charge of less than 80 and never have the opportunity to receive a full charge That may

    Original URL path: http://www.hefra.nl/docs/webshop.asp?act=doc&id=4792 (2016-05-01)
    Open archived version from archive

  • Hefra - Technical info - Thermal Runaway
    as a battery meltdown It s a phenomenon that in lead acid batteries only find VRLA batteries The chemical reaction of the recombination process in a Valve Regulated battery is an exothermic process it generates heat When a battery is overcharged in high ambient temperature the exothermic process will increase the temperature within the battery faster than can be dissipated The increasing temperature will decrease the charging voltage and at

    Original URL path: http://www.hefra.nl/docs/webshop.asp?act=doc&id=4794 (2016-05-01)
    Open archived version from archive

  • Hefra - About batteries: the primary cell
    lead Battery type application In 1786 biologist Luigi Galvani dissected a frog Every time Galvani s steel scalpel touched a brass hook that was holding the frog s leg in place the leg would twich Galvani believed that this energy came from within the animal and called it animal electricity Galvani s friend and associate Alessandro Volta disagreed He was convinced that the electricity was generated by the two dissimilar

    Original URL path: http://www.hefra.nl/docs/webshop.asp?act=doc&id=4805 (2016-05-01)
    Open archived version from archive