Rechargeable PP3 battery for onboard booost

DannyP

I have a project in mind to house the battery for an onboard boost in an unused pickup rout under the pickguard.

Clearly, this will mean that the battery will be hard to access.

I hit on the idea of using a rechargeable battery and connecting it to a discreet lead or sock that could be accessed from the back and connected to a charger.

My question is: could the connection from battery to charger AND the connection to the boost PCB both be hard wired to the battery clip?

...or would this cause problems while charging? Would I need a switch to go between 'play' mode and 'charge' mode - switching the battery clip connection between the charger and the boost PCB so the aren't both permanently connected?

I hope this makes sense??!?

Ta

Dan

DannyP

I'm not planning to play and charge up the battery at the same time by the way!!

ICBM

If you connect the battery negative to the ring terminal of a 'stereo' jack - as normal to turn the circuit on only when a plug is in the jack - then if you connect the charging lead directly to both poles of the battery, you can charge the battery without the circuit being on.

In fact, I think if you put a diode from battery positive to ground, you can then charge the battery via the output jack, using a stereo plug with the charger negative connected to the ring and the positive to ground (no connection to tip), and you won't even need another connector.

DannyP

Ah OK - I was going to do the stereo jack thing anyway, but my mind hadn't made the connection between that and solving my charging puzzle!

The boost would be something from Fuzz Dog (formerly Poodle Pedal Parts) - maybe the Alembic Stratoblaster.

I had the idea of picking up a Squier Custom and turning it in to an Esquire, but using the extra pickup rout and cavity space to add some fun stuff. More as a knock-about budget project rather than a be-all-and-end-all dream guitar!

Many thanks as ever ICBM.

ecc83

From the battery to the circuit fit a 10R wee fusible resistor, or a Wickman fuse.

Problem with re-chargeable (SLA?) PP3s is that their internal resistance is bugger all and they can output huge currents, vastly in excess of the circuit demand and so if the circuit shorts in some way, a cap or chip, the battery will get very hot, swell up and bugger itself and all about it. Might even catch fire!

I have had this happen in a digital meter.

Dave.

GuyBoden

The problem is you'll have to wait until the battery is recharged to play the guitar, so it would be better if you cut a neat hole in the back with a cover to access/replace the battery.