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--></style></head><body lang="EN-US" link="#0563C1" vlink="#954F72"><div class="WordSection1"><p class="MsoNormal">Lesson relearned on NiCd charging: Several years ago I made three 12v batteries from D cell NiCd’s.</p><p class="MsoNormal"> </p><p class="MsoNormal">They have been a huge disappointment. They are only used once or twice a year on critical field work and always fail far earlier than estimates. But I always just charge them the night before with a fixed voltage charge of 14 volts since I most often forget about batteries I put on charge and end up ruining most of them. Charging at fixed voltage is safe…</p><p class="MsoNormal"> </p><p class="MsoNormal">For the AT Golden Packet event tomorrow, last night I left them on my usual 14 volt overnight charge and they were “fully charged” by morning, only drawing a 50 mAh each in the morning at 14 volts..</p><p class="MsoNormal"> </p><p class="MsoNormal">Put them on a battery analyzer and their capacities came in at 10%, 8% and 3%. Then the battery analyzer quick charged them at 1C rate for 1 hour with them getting up to 16 or 18 volts, then a 4 hour equalization charge of 0.1C or 400 mA. </p><p class="MsoNormal"> </p><p class="MsoNormal">Then it retested them and got 75%, 65% and 85% of rated capacity!</p><p class="MsoNormal"> </p><p class="MsoNormal">So, Apparently little-used NiCd’s are not going to get a good charge from a FIXED voltage charge!</p><p class="MsoNormal"> </p><p class="MsoNormal">Wish I had time to cycle them two more times. On batteries at work we see huge recoveries from little used NiCd’s when “rejuvenated” which is the 3 cycles of charge and discharge I started with above.</p><p class="MsoNormal"> </p><p class="MsoNormal">Bob</p></div></body></html>