custom cellphone battery charger drains out the cellphone battery..why??

I made a cellphone battery charger from 3 AA batteries.The combination of 3 AA batteries was at a higher potential than the cellphone battery, but when i connected both of them for charging, the potential of 3 AA batteries remained same but the cellphone battery was completely drained.why??If someone could explain maybe??

iceng10 months ago
  • You do not have the schottky diode wired correctly
  • The charge current limiter is actually drawing the CB
  • AA batteries are No-load voltage high but discharged
  • Connector wired to  the wrong bins.

These are some of your possible problems when there is a utter lack of
information beyond the main complaint and we have to use the
Jedi remote viewing to see your schematic
chatsbk007 (author) 10 months ago
aa battery charger schematic.png
iceng chatsbk00710 months ago
A low forward diode prevents reverse discharge.
chatsbk007 (author)  iceng10 months ago
a 1N4007 will do, i suppose
I already have it at home
iceng chatsbk00710 months ago
While a 1N4007 will do as well as a 1N4001.
A 16¢ 3A 40V schottky diode with a lower forward drop can charge a little bit more.

Thanks for selecting my answer.

chatsbk007 (author)  iceng10 months ago
i got it now ...thanks
chatsbk007 (author) 10 months ago
the batteries were connected in series
+ve of 3 AA batteries was connected to +ve of cellphone battery and -ve of 3 AA battery was connected to -ve of cellphone battery
iceng chatsbk00710 months ago
What is the voltage when you have them hooked up together Without the electronic one way valve special diode I texted about ??
chatsbk007 (author)  iceng10 months ago
4.44 V
chatsbk007 (author)  chatsbk00710 months ago
wid the multimeter
i dint get the spl diode way
chatsbk007 (author) 10 months ago
wires are not connected to wrong pins certainly
and i dont think they are no load voltage cz they lit a number of leds
here are the circuit and led lighting
Picks help
chatsbk007 (author) 10 months ago
potential of 3 AA batteries(4.44V) was higher than cellphone battery(was lesser than 2.5V)
kelseymh10 months ago
Did you connect the batteries in series (for a total of 4.5 V), or in parallel (for more current, but only 1.5 V)? The charger must have a higher voltage (usually significantly higher) than the battery being charged.
WWC10 months ago
Can you show your schematic?

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