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NiCad batteries

I do not recommend the purchase of surplus NiCad batteries as NiCad batteries are generally very susceptible to ``memory'' effects and other possible malfunction. Consequently, those found in salvage equipment are generally found in a state of malfunction already.

A new ``battery vest'' may be purchased for around $600 (see This solution has the advantage of providing a ready-to-wear power supply without the need to devise one's own solution. Furthermore, the vest provides plenty of pockets for placement of computational apparatus, etc., and provides a good means of physical placement of the additional components. These vests are designed for high-current output (e.g. video lights and large cameras), so it is advisable to include an additional fuse of lower current rating, consistent with the actual usage patterns expected.

Alternatively, one can purchase new NiCad packs for under $100 and sew them into a vest or the like. Again, make sure the batteries are fused properly and well insulated as there is an extreme fire hazard owing to their high short-circuit current capability, and the potential hazard is multiplied by the effect of close proximity to the body, and potential difficult of removing the apparatus or undressing quickly enough to avoid being trapped in burning material.

Steve Mann
Wed Dec 24 05:46:06 EST 1997