NICKEL - CADMIUM FOR ECONOMY. Continued.
By Bob Grimes. Area 20.
I read with great interest Eric Clark`s article about the Nic Cad cell in the October 88 issue of the Newsletter.
I have used these cells for all my equipment for several years, paying attention of course, to the remarks about using them by some manufacturers, if they say don`t use them. then I haven`t, although having said that and electronics relative of mine completely ignores this and uses this type of cell be it recommended or not, I hasten to add that to-date no equipment has suffered as a result of his using the `forbidden` cells. Fortunately for me, at any rate, the equipment I use most are not of the `forbidden` variety.
Amongst the nic cads that I have are those made by: Yuasa, Varta (under the Chemists brand name), Marathon (from Jessop of Leicester) and Sunpack. The latter differs from the others mentioned in that they are quick charge cells and need only three to four hours of charging, no harm can come to them at this quick charge rate as they are designed for the quick charge.
Like most things in life I have found these vary to a great degree in their efficiency and I have found the best of the slow charge cells are the Yuasa and the Varta ones are the worst. My remarks are based on the heavy usage of flash guns, I take most of my flash pictures with two guns, one dedicated on the camera with TTl facilities and a `slave` gun set to manual and usually bounced off the ceiling. The best cell by far is the Sunpack quick charge, these will still be alright after six rolls of 36 exposure film has been used. I accept of course whilst on manual the other cells deliver maximum power, but having dais that, I do swap them around and my findings remain the same. The quick charge batteries are slightly more expensive than the rest. But, as Eric rightly writes, the initial cost soon repays you.
However, the above is not really what prompted this reply to Eric`s article. In fact, he left out one very important point and it is one that I have to admit, until recently, I was unaware of what you should really do with rechargeable cells.
Assuming that a few days ago you used your nic cads for some purpose or other, and now tomorrow say, you expect to use them for a considerable period, it is quite sensible to think that it would be a very good idea to put the cells on charge to `top` them up. DON`T, apparently this is the worst thing you can do to them, you should make certain they are fully discharged before recharging. Even if your flash gun fails to work, there is still considerable power left in them to operate say a small torch and having read the article about these cells in the Pentax magazine I now put them in a small pocket torch and drain them completely. I have tried putting them in a personal cassette player but so little power is used on these that it takes ages to discharge.
Having made that point I now wonder of course, if my remarks earlier about which cell I consider to be the best are based on theory that perhaps because I am guilty of `topping` them up, I may have shortened their life? However, I now charge in the recommended manner.
If I charge a dozen cells today, will they still be fully charged in about a weeks time or is it best to charge them just before you need them which is not often practical as you may need to use them long before the 14 - 16 hour charge period has elapsed!