power supply
 

i have a few 12V, 2.3Ah rechargable batteries. can i safely
use them for a power supply for a 12V charger when i go places with my car that i can't get access to electricity? i used it once and when i finished it wasn't warm and i checked it with my digital voltometer and it was at 9V.

Thanks in advance

A 2.3 amp hour battery will not be large enough to charge a 7.2v or 6 cell R/C battery. You will need at least a 15 amp hour or larger to provide sufficient power to you charger. With a 15 amp hour battery you may get 3 charges out of it provided the 15 amp hour battery was fully charged itself. A car battery will work well but they are large and heavy. Most common car batteries are 65 to 100 amp hour. Good luck;)

sir maybe you could help me with my problem!
i have a 12V (actually it's 17.5+V i checked it with my multimeter) 12Amp power automotive charger/converter and i'm planning of using it on my LRP Micro Charger, is 12Amps too much for my charger?

Your automotive battery charger will not make a good power supply. The no load voltage is too high. That is with nothing drawing current the voltage will be 17.5 volts unfiltered DC. You may damage your R/C battery charger. Typically the highest voltage you would want to run is no more than 14.5 volts. The current rating (Amps) just needs to be sufficient to charge you battery. If you are going to charge your battery at 5 amps your power supply needs to be able to deliver at least 5 amps. Having a power supply that has a higher current ratting is good. This gives you "head room" and you will not stress you power supply out. You want to look for a Filtered Regulated 13.8 to 14.5 volt power supply with 7 to 10 amp current rating. Filtered means there are large filter capacitors that take the ripple out of the rectified AC voltage. This makes the DC power from your supply smooth and clean. Regulated means the voltage will be stable and will not change under various loads. When you not charging a battery the voltage will read lets say 14.0 volts and when you are at 5 or so amps the voltage will stay at 14.0 volts. This filtered and regulated power is necessary for most modern "Peak" type chargers. In order for the charger to accurately determine the charge they need a stable and clean input power. Tip I have never seen an unfiltered regulated power supply. If it is regulated it is filtered.

now i understand, thanks a lot sir!