Thinking about an HP-41CL

[Dave Frederickson]

(07-28-2016 05:51 PM)Dieter Wrote:  

(07-28-2016 04:41 PM)Dave Frederickson Wrote:  Here's the GP50NH dartasheet:

Fine, but since the GP50NH is no longer available most probably a different type of battery will be used. ;-)

Agreed, but the datasheet is a representative example of a typical 500mAH NiMH N-cell, and it's what Sylvain recommended.

(07-28-2016 05:51 PM)Dieter Wrote:  

(07-28-2016 04:41 PM)Dave Frederickson Wrote:  A couple of questions. The BC-700 also detects end-of-charge by temperature, and the datasheet shows a DT/dt spec. Will the BC-700 end the charge cycle properly if the cells are charged at 200mA rather than fast-charging at 250 to 500mA?

But where do you see a graph with dT/dt specifications?

There are some values for dT/dt in the GP50NH datasheet.

(07-28-2016 05:51 PM)Dieter Wrote:  

(07-28-2016 04:41 PM)Dave Frederickson Wrote:  Yesterday I received some 2200mAH AA flat top cells for use in Spice calcs. (No, they won't make contact with the charger without a washer.) Initial research turned up a 2200mAH Sub-C cell with a normal charge current of 220mA. Without buying the higher current BC-1000, what's the best charge current?

But how do you want to squeeze a SC cell into a Spice, or even the BC700?

I simply found a datasheet for a SC cell. It provided some ballpark specs until I could find an AA datasheet.

(07-28-2016 05:51 PM)Dieter Wrote:  

(07-28-2016 04:41 PM)Dave Frederickson Wrote:  It would be nice if someone wrote an article about smart chargers and high-capacity cells.

What high-capacity cells do you refer to?

Any cell that is not practical to charge on the original ~50mA charger that came with the calculator.

Dave