Hi All,
A few months back I bought a really nice hand held spotlight and last night it crapped out on me. I put it on charge and this morning it was still dea d so I opened it up. A small 2.3AH, 6-volt sealed battery and a wall-wart c harger with the prongs facing out of the back. A bit of a visual surprise.
A bit of poking around and the wal-wart (6vdc 300ma) is a done for. I have a 7vdc 700ma wall wart that I am hoping I can use. The original had no char ging controller, the output went straight to the battery. I am hoping I can do the same with the 7vdc.
No load output was 11vdc. Clipping to the battery it drops to 8.4vdc and as I watched, about every 20-seconds the voltage would drop 0.01v. Not sure w hy but then I am a **Mechanical** Engineer. {grin}
Nothing got hot after 5-minutes, with the charger removed, the battery was already holding 5.4vdc, so I am guessing that is still OK.
The questions.
1: Should I have a resistor as a current limiter? If so what value and wattage ? 2: Is it OK to just let the 7vdc supply just feed into the battery? Providing of course I unplug it after a reasonable amount of time? 3: Will the battery and charger find a balance at somewhere around 7v when the battery is fully charged?This is a really good light when it was working and I am reluctant to spend anther 60-bucks when it is only a charging problem.
Useful suggestions?
Thanks