I wonder if a zener diode in series with a resistor wouldn't provide the discharge capability and some protection from taking the battery down to nothing. Resistor would have to be selected with the power handling ability of the zener - don't forget the power rating of the resistor itself.
Nigel , is the safe discharge for batteries worked to a percent of full charge ( eg . a new car batt fully discharged a few times seems to wreck them ) ,,?? .. Also a mate of mine got a mobile phone the same as mine ,(same shop, one day later , and his batt died a few months ago and mine's still goin strong ),(touch my head)..
Nigel , is the safe discharge for batteries worked to a percent of full charge ( eg . a new car batt fully discharged a few times seems to wreck them ) ,,?? .. Also a mate of mine got a mobile phone the same as mine ,(same shop, one day later , and his batt died a few months ago and mine's still goin strong ),(touch my head)..
The spec for rechargeable batteries usually specify the minimum recommended discharge point. As for phones, they usually don't treat the battery very well, so it's quite easy for the battery to fail fairly early.
I wonder if a zener diode in series with a resistor wouldn't provide the discharge capability and some protection from taking the battery down to nothing. Resistor would have to be selected with the power handling ability of the zener - don't forget the power rating of the resistor itself.
I'm not sure about this, but I think the reason behind only discharging to a certain point is so that cell reversal won't occur which can permanentl affect the cell. If that's the case, I think discharging down to several hundred millivolts would probably be ok. Instead of the zener just put a silicon rectifier diode in series with the resistor and you could discharge down to about 0.7 volts. Or depending on what the spec sheet says, just several diodes or one zener like Stevez suggested.