Battery switch

Started by W. eWatson in sci.electronics.basics8 years ago 8 replies

I bought a device that will allow me to undo a plastic knob and disconnect my battery. Should I put it on the ground or hot cable? The only...

I bought a device that will allow me to undo a plastic knob and disconnect my battery. Should I put it on the ground or hot cable? The only negative affect seems to be that I would need to reset the clock each time I reconnected the battery; otherwise, I would think that no harm would come to the electronics. Recently, it's gotten bad enough that it drained my battery. I'm doing thi...


Keeping a 12v battery charged above 80%

Started by W. eWatson in sci.electronics.basics8 years ago 22 replies

I had a fellow out to do some electrical work that involves one 12v marine battery. The battery will be used about 4-6 hours a night...

I had a fellow out to do some electrical work that involves one 12v marine battery. The battery will be used about 4-6 hours a night sporadically. Maybe 15-20% of the time. He offered that it should be recharged every day, and keeping it above 80% was important for the life of the battery. Somehow that seems a bit high. Apparently, there's a charger of some sort that costs about $150 th...


Battery parallel connection ?

Started by mowhoong in sci.electronics.basics8 years ago 2 replies

Parallel connection on lantern batterys will have higher current, but it wi= ll cause self dicharge to other battery with lower voltage. My...

Parallel connection on lantern batterys will have higher current, but it wi= ll cause self dicharge to other battery with lower voltage. My solution to = solve this problem was to add one diode to each battery, but I do not know = why this method was not used on commerical battery pad ? Can any members of= this group give me me advice. Thank you and happy x'mas to all members. Regards


Battery Selection

Started by OldGuy in sci.electronics.basics5 years ago 5 replies

I need to run my laptop for many hours and in a mobile state; i.e. no AC Power available not car available. I have a Enercel AC/12VDC to...

I need to run my laptop for many hours and in a mobile state; i.e. no AC Power available not car available. I have a Enercel AC/12VDC to laptop power block cord. What is the best battery to use with this other than a full size car battery. I have been looking at closed cell 12v 18AHr batteris as a possible choice. not sure is these are deep discharge. Or maybe a motorcycle battery...


PWM from raspberry pi to control charging of a 12 V Battery, possible?

Started by Anonymous in sci.electronics.basics7 years ago 2 replies

Hi there, I just got a raspberry pi and was wondering if it is possible to use its PWM output to control current flow to a 12 V Battery (with...

Hi there, I just got a raspberry pi and was wondering if it is possible to use its PWM output to control current flow to a 12 V Battery (with an IGBT). My idea is to use a 300 W windmill, a simple AC/DC converter, a IGBT, and the battery at the other side. If voltage is above 13.8V, I reduce the current via PWM to fully charge the battery and disconnect the windmill as soon as the battery ...


Battery choice: 9V vs 6 AAs

Started by Adam Funk in sci.electronics.basics5 years ago 35 replies

I'm fixing a kid's toy that was damaged by corrosion (stored with the batteries). The only damaged part was the battery compartment, so...

I'm fixing a kid's toy that was damaged by corrosion (stored with the batteries). The only damaged part was the battery compartment, so I opened it up, clipped off the internal wires to that bit, soldered extensions on them & ran those through holes in the case, in order to put an external 6 AA holder on. As it turns out, the 6 AA battery holder I bought clips onto a 9 V battery attachment,...


Battery charging question...

Started by Dave in sci.electronics.basics5 years ago 8 replies

Just a quick question, but aren't we supposed to charge a rechargable battery gy sending current through it in reverse to the normal polarity of...

Just a quick question, but aren't we supposed to charge a rechargable battery gy sending current through it in reverse to the normal polarity of the battery? Just wondering why it doesn't seem to be working... Thanks


AA battery dead with debris

Started by W. eWatson in sci.electronics.basics8 years ago 4 replies

I have a one foot diameter clock with a AA battery. I noticed it had stopped. I looked at the back, and found white power had seeped out of...

I have a one foot diameter clock with a AA battery. I noticed it had stopped. I looked at the back, and found white power had seeped out of battery. I don't think it's acidic, and I know the regular trash pick up will take such batteries. What's the best way to clean up the mess to put in a new AA?


Charging an alarm battery

Started by W. eWatson in sci.electronics.basics8 years ago 4 replies

I have a Xantrex 12v rechargeable 600 Power Pack battery. Yesterday I charged it up and then attached a 12v smaller alarm battery. I forgot...

I have a Xantrex 12v rechargeable 600 Power Pack battery. Yesterday I charged it up and then attached a 12v smaller alarm battery. I forgot to check a few hours later. However, 8 hours later I disconnected the two and found the alarm battery at 11.1 volts, and the Xantrex at 0%. I'm recharging the Xantrex now. Did I somehow harm it?


So, how DO I charge a 6V SLA battery?

Started by Anonymous in sci.electronics.basics12 years ago 26 replies

I bought a 6V, 6Ah battery from Home Depot to power my 3-year-old's toy electric car (the kind that a kid can ride). The previous...

I bought a 6V, 6Ah battery from Home Depot to power my 3-year-old's toy electric car (the kind that a kid can ride). The previous battery didn't hold a charge when I bought the car. One reference from batteryuniversity.com mentioned something about 2.50V per cell for SLA batteries. I'm assuming my battery has 3 cells. Another website mentions use of an L200 voltage regulating chip (http...


stepping up battery voltage

Started by Igor in sci.electronics.basics7 years ago 13 replies

Hi. I want to step up voltage of my AA 1,5 battery to 2.5V but i need to limit the current to 500mA. Ampmeter shows that the current of the...

Hi. I want to step up voltage of my AA 1,5 battery to 2.5V but i need to limit the current to 500mA. Ampmeter shows that the current of the battery is around 6A and dropping to 3A. How to make this 2.5 / 0.5A output ?


18650 battery holder

Started by Andy in sci.electronics.basics1 year ago 4 replies

Is this the right battery holder so that I get 3.7...

Is this the right battery holder so that I get 3.7 volts? https://www.ebay.com/itm/5Pcs-Empty-1-2-4-Cells-Li-Batteries-w-Wire-Leads-for-18650-Battery-Hold ers/132730830743?hash=item1ee75fbf97:m:mBZqCocJbuoDRghrmatEjaQ:rk:17:pf:0 Thanks.


Kirkland Marine Deep Cycle Battery

Started by W. eWatson in sci.electronics.basics5 years ago 6 replies

About two years ago I bought the Kirkland battery in Subject. Unfortunately, the project I had intended it for never developed. However, I...

About two years ago I bought the Kirkland battery in Subject. Unfortunately, the project I had intended it for never developed. However, I have had it on a trickle charge for a good bit of that time. The battery probably cost about $100. I'm looking at the possibility of selling it locally. Would it still be useful at close to its initial usefulness?


Power solutions for 9V battery

Started by Douglas Beeson in sci.electronics.basics6 years ago 15 replies

Hi all, I need to generate +15 V and -15 V (just a few mA), as well as standard 5V (about 50 mA), from a 9V battery. I am bewildered by the...

Hi all, I need to generate +15 V and -15 V (just a few mA), as well as standard 5V (about 50 mA), from a 9V battery. I am bewildered by the range of solutions available. I have used LDOs many times, but am discouraged by their low efficiency for this battery-powered project. I have looked at the LT1054 capacitor-based voltage regulator, and like its simplicity and ability to generate both + ...


75332P MOSFET drain connected to which battery terminal?

Started by John Doe in sci.electronics.basics8 years ago 11 replies

I have a 75332P MOSFET on a cordless drill controller heatsink. I guess it's part of a pulse width modulator. The drain (flange) connects...

I have a 75332P MOSFET on a cordless drill controller heatsink. I guess it's part of a pulse width modulator. The drain (flange) connects directly to one of the battery terminals. Does the MOSFET drain go directly to the battery minus/ground terminal? Or does it go to the battery plus terminal? Thanks. -- My application... I'm desperately trying to develop a better inline ...


Charging a marine battery

Started by W. eWatson in sci.electronics.basics8 years ago 31 replies

About 3 months ago, I purchased a deep cycle marine battery (12v) from Costco. It probably weighs 60 pounds. The application I intended for it...

About 3 months ago, I purchased a deep cycle marine battery (12v) from Costco. It probably weighs 60 pounds. The application I intended for it is slowly proceeding, and I haven't used the battery at all. Any suggestions for charging it? I'll check the voltage tomorrow. It may not need it yet. That reminds me, the June issue of Consumer Reports has an article about using an inverter wi...


Removing battery corrosion

Started by Anonymous in sci.electronics.basics2 years ago 19 replies

I got an old AM-FM pocket transistor radio which looked good and clean till I opened the battery compartment. Very corroded carbon...

I got an old AM-FM pocket transistor radio which looked good and clean till I opened the battery compartment. Very corroded carbon zinc batteries were in it. After removing them, I cleaned off as much of the corrosion as possible by scraping with a plastic stick, and scrubbing with q-tips and rubbing alcohol. That got rid of most of it, and I was surprised to find the battery clips are not ba...


Need, maybe found, low voltage latching circuit

Started by Anonymous in sci.electronics.basics6 years ago 3 replies

All, I have an expensive measuring tool that is powered by the ubiquitous SR44 silver oxide battery. The tool doesn't get used much but when...

All, I have an expensive measuring tool that is powered by the ubiquitous SR44 silver oxide battery. The tool doesn't get used much but when I do go to use it the battery voltage has always dropped enough to cause the display to flash. So I always remove the battery when I put the tool away. This is a pain. I thought about putting in a tiny toggle switch but there is not room in the electron...


OT Lipo battery charger

Started by George Herold in sci.electronics.basics4 years ago 1 reply

So my son is into RC... He's bought some old RC cars back to life and watns to run them with new Lipo batteries. We are now looking for a...

So my son is into RC... He's bought some old RC cars back to life and watns to run them with new Lipo batteries. We are now looking for a battery charger. Any recommendations? price ~$100. This one in particular, http://www.ebay.com/itm/Venom-Pro-Duo-80W-X2-Dual-AC-DC-7A-LiPo-NiMH-RC-Battery-Balance-Charger- /401004922785 TIA George H.


Help with battery installation

Started by Meanie in sci.electronics.basics7 years ago 8 replies

My wife has an electric yarn spinner which operates from 120v outlet and converts to a 12v 1.2 amp(max)DC power. Per the manufacturer, amps are...

My wife has an electric yarn spinner which operates from 120v outlet and converts to a 12v 1.2 amp(max)DC power. Per the manufacturer, amps are typically running at .5. I want to provide a power source without the required need for a power cord. Therefore, the obvious solution is battery power. The confusion lies with the amps. I know all AAA, AA, C and D size battery outputs are 1.5 ...