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Gallery, Projects and General => How do I?? => Topic started by: shipto on June 21, 2019, 01:58:36 PM

Title: Bosch charger
Post by: shipto on June 21, 2019, 01:58:36 PM

I wonder if anyone can help me. I am trying to make a battery pack from Bosch Nimh battery packs and plan to alter a AL 2450 DV charger to charge it. I have constructed the pack to deliver 24V but when I put the pack on the charger it indicated fully charged at 18V.
How does the 7.2V to 24V charger detect the voltage of the battery plugged into it? At first I thought the component that connects on the third connector was just to monitor the battery temperature but maybe it does more than that?

Title: Re: Bosch charger
Post by: mc on June 21, 2019, 03:12:44 PM

Older Nimh packs I would have thought the same, however they may contain some form of microchip, with the 3rd connector being used for serial communication between the battery pack and charger.

Title: Re: Bosch charger
Post by: shipto on June 21, 2019, 04:48:47 PM

Possible I guess but I dont think its the case, the component just looks like a thermister? It has a resistor in series so maybe the resistance determines the voltage for the pack? thats just come to me actually because the thermister from a 14.4V was different to the ones from the 18V. My first thought was it was a older battery pack, I have been searching but cant find much info specific to Bosch.