Bosch Gbh 24 Vre Battery
Many years ago, NASA did a study on NiCad batteries, where they
documented a "memory" effect. What they found was that NiCad batteries
would tend to "remember" the previous level of discharge, and that if
the batteries were repeatedly discharged to that same point (let's say
only 20% of the charge was used each time), that the battery would
subsequently tend to rapidly lose capacity after 20% of the charge was
used. Over the years, however, battery companies improved NiCad batteries such
that the memory effect was no longera significant concern. But that
same study is quoted time and time again, and entire companies have
sprung up tmanufacture "battery exercisers" to automatically discharge
and recharge NiCads. As for "fully" discharging NiCads, you should actually avoid doing that.
The reason is because that 24 volt battery is made up of about 18
batteries wired in series. Since it's nearly impossible to make 18
batteries that are EXACTLY alike in capacity, it's likely that during a
full discharge, the weakest one will actually undergo a "reverse" charge
by the remaining healthier batteries. Once a NiCad is
reverse-charged, it's capacity will be even more degraded, increasing
the potential (no pun intended) for future reverse-charge incidents. Manufacturers of NiCads were (at one time) recommending discharging only
to the half power point (if I recall correctly), which is roughly about
where you notice the tool is beginning to become a little weak. Now, besides all of that, you should also not err on the side of
over-doing the charging thing. Many simple battery chargers do not
shut off when the battery is fully charged. A battery pack left on one
of those will begin to heat up when it's fully charged, and that is
also bad for the cells as it can damage the electrolyte.
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