Growth of Metal Through Battery Separators

Apart from the nanobarrier page, this presentation is silent on the subject of battery plate separators. Teardowns of the batteries used in the evaluation depicted in Graphs 1 and 2 were performed on completion of the testing. These revealed that lead metal had accumulated in the pores of the separators in respect of the “Plain” set of batteries and that this accumulation had contributed to shorting out or bridging between the negative and positive battery plates. The “Batteryvitamin” set of batteries did not appear to have accumulated anywhere near as much lead metal in the separator pores.

In this experiment a negative electrode made of a doubled over length of tin wire is suitably boxed in against the reverse surface, as viewed, of a section of polyethylene separator sheet, the rest of the cell being arranged generally in accordance with the second experiment.

This movie shows fine particulate of metal seemingly being exuded from the surface of the separator sheet in line with the negative electrode located behind the sheet. What is actually happening is that metal is being progressively electroplated onto the negative electrode along a path offering least resistance between the positive and negative electrodes.

Metal ions arriving at the negative electrodes after having migrated from the positive electrodes and having wound their way through the separator pores build tentacles of ever increasing lengths via the separator pores until the on plating process becomes visible on the other side. Clumps of fine metal particulate can be seen breaking off as gravity takes over, only to grow again.

This would seem to be implying that as such, the barrier provided by the separators in batteries might only be partially effective. Batteryvitamin can be very useful in helping to control this undesirable effect.

TEST EQUIPMENT

Regular 12V automotive battery, for use as power supply;
150 ohm, 2 watt resistor, as current regulator.


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Lead-acid motive power battery business breakthrough.