Why is DeWalt's new battery so big?

Started by John Doe in sci.electronics.design2 years ago 15 replies

Their 6 amp hour (regular, not flexvolt) battery is 41% heavier and at least that much bigger than their 5 amp hour battery. Over 40% bigger...

Their 6 amp hour (regular, not flexvolt) battery is 41% heavier and at least that much bigger than their 5 amp hour battery. Over 40% bigger and heavier for 20% more capacity???


Forever Power (almost)

Started by Anonymous in sci.electronics.design3 years ago 27 replies

This is just a stupid idea that I had, which will acomplish nothing, other than see how long it lasts. I dont know how much a standard 12V 5...

This is just a stupid idea that I had, which will acomplish nothing, other than see how long it lasts. I dont know how much a standard 12V 5 amp battery charger requires from the 120Vac power line, but I read it was around 150 watts. So, lets say I connect a 200W inverter to a car battery. Then plug into that inverter, a 12V 5A battery charger, and connect the leads from that charger to...


A bit of fuzzy logic

Started by Jan Panteltje in sci.electronics.design6 years ago 1 reply

A bit of fuzzy logic Needed a circuit that disconnects the Lipo battery from my solar powered geiger counter SDcard logger when Lipo...

A bit of fuzzy logic Needed a circuit that disconnects the Lipo battery from my solar powered geiger counter SDcard logger when Lipo voltage drops to below about 3.1 V, this to protect that battery. Had already decided to use an IRLZ34N logic level MOSFET, but how to drive it? Once per minute the PIC microcontroller measures the battery voltage, resolution about 2 mV, and a #define...


PIR sensor reacts on power

Started by Sonnich Jensen in sci.electronics.design5 years ago 3 replies

Hi all I bought an MP PIR sensor on eBay...

Hi all I bought an MP PIR sensor on eBay ( http://www.ebay.com/sch/i.html?_from=R40&_trksid=p2050601.m570.l1313.TR0.TRC0.H0.Xmp+pir.TRS0&_n kw=mp+pir&_sacat=0 ), which works well, except when plugged in It has its owns battery, and works well when working on battery, but when I plug it in (I need it for longer time that the battery lasts), then it will contact me quite often. It uses a USB m


craftsman 240v welder buzzbox battery charger

Started by Yzordderrex in sci.electronics.design7 years ago 10 replies

I've got a little spare time here at work today so I ran a simulation to us= e welder as interface between 120v line and 12v car battery. It...

I've got a little spare time here at work today so I ran a simulation to us= e welder as interface between 120v line and 12v car battery. It looks like= I can probably put welder on 120v line with a single phase diode bridge on= it and use current knob on welder to control current to charge 12v battery= . Am I totally nuts or Mcguyver?


Charging time for Ultrafire 18650 6800 mAh battery

Started by Andy in sci.electronics.design2 years ago 44 replies

I would like to find out how long to charge the above battery. Charger puts out 500 mAh. Thanks.

I would like to find out how long to charge the above battery. Charger puts out 500 mAh. Thanks.


Replace Li Ion battery

Started by Andy in sci.electronics.design3 years ago 27 replies

I want to replace a LiIon battery with a high capacity one. The old one has a third yellow wire. What is it for ? Thanks, Andy

I want to replace a LiIon battery with a high capacity one. The old one has a third yellow wire. What is it for ? Thanks, Andy


Auto-detecting battery power for circuit

Started by panfilero in sci.electronics.design9 years ago 45 replies

Hello, I have a circuit that works off of 3V. I get the 3V in two different ways, one is through a 9V battery that plugs into a DC power...

Hello, I have a circuit that works off of 3V. I get the 3V in two different ways, one is through a 9V battery that plugs into a DC power barrel receptacle that goes to a 3V regulator, and the other is from a 3V pin that is available on the circuit. I'm wondering if there is a way the circuit could automatically use the 3V pin if there's no battery plugged into the DC barrel receptacle, a...


Is lithium ion battery technology still not there?

Started by cameo in sci.electronics.design7 years ago 57 replies

Boeing has a hell of a time with fixing its battery problem on the 787 Dreamliner. I wonder if any of you had a deeper knowledge as to the...

Boeing has a hell of a time with fixing its battery problem on the 787 Dreamliner. I wonder if any of you had a deeper knowledge as to the cause and whether those batteries are just not yet a proven technology.


DSO to measure charging battery?

Started by John Doe in sci.electronics.design2 years ago 20 replies

On a typical DSO, can you specify some number of minutes or hours range and then have it continuously plot the voltage of a battery being...

On a typical DSO, can you specify some number of minutes or hours range and then have it continuously plot the voltage of a battery being charged? I have looked around but haven't seen that. Thanks.


How does this balance charger battery sensing work?

Started by John Doe in sci.electronics.design3 years ago 2 replies

My writing below the link might be more concise. I bought a "balance charger" that allegedly tries to evenly charge every cell in a battery...

My writing below the link might be more concise. I bought a "balance charger" that allegedly tries to evenly charge every cell in a battery pack. Apparently the individual cell voltages are correctly displayed. The battery pack to be charged has four wires. It is connected to the "balance charger" as in the links below. The balance charger has four sensing circuit leads, two of them ...


Using an AA battery charger to charge D cells

Started by Anonymous in sci.electronics.design2 years ago 11 replies

I have a battery charger which only fits AA and AAA batteries. I recently bought a Maglight flashlight, which uses three D cells. I want to put...

I have a battery charger which only fits AA and AAA batteries. I recently bought a Maglight flashlight, which uses three D cells. I want to put rechargable batteries in it, but I have no way of charging them, unless I buy another (expensive) charger. It seems that almost all battery chargers these days are only for the AA and AAA batteries. There are only a few that charge the C and D cells, ...


Sizing a battery charger

Started by G. Morgan in sci.electronics.design8 years ago 35 replies

What is a good formula for the needed minimum current (and over voltage) for charging batteries? Use a 12V car battery for example, how...

What is a good formula for the needed minimum current (and over voltage) for charging batteries? Use a 12V car battery for example, how much 'trickle charge' is needed to keep them alive when not being used? Thanks.


RTC and cr2032 low voltage

Started by captoro in sci.electronics.design8 years ago 2 replies

Hi, I am using the RTC DS1337 with a CR2032 battery. I know that when these battery shows 2.7v, it needs replacing, Although the RTC can...

Hi, I am using the RTC DS1337 with a CR2032 battery. I know that when these battery shows 2.7v, it needs replacing, Although the RTC can go down to 1.4V from the spec sheet. I even powered it through my power supply at 1.1V and it was keeping time correctly. I am only power the RTC from the battery. My question is : How low of a voltage can I go before replacing in a real life situation ? ...


How to increase lithium-ion battery pack life?

Started by John Doe in sci.electronics.design9 years ago 17 replies

Does a high-quality commercial tool do enough to prolong the life of its lithium-ion battery pack? Should they be recharged whenever...

Does a high-quality commercial tool do enough to prolong the life of its lithium-ion battery pack? Should they be recharged whenever convenient instead of waiting until the tool requires recharging? I just had a lithium-ion battery pack die before it's time. I'm wondering if better handling would have prolonged its life. Seems that one of the 3 cells switched off. One cell is 3.75 ...


Will a dimmer switch work instead of an incandescent light bulb in a simple battery charger?

Started by Anonymous in sci.electronics.design7 years ago 42 replies

The other day, I came upon this: http://www.alpharubicon.com/elect/3dollarb= attggn.htm It's plans for a very simple battery charger that uses...

The other day, I came upon this: http://www.alpharubicon.com/elect/3dollarb= attggn.htm It's plans for a very simple battery charger that uses a light bulb and dio= de in series to make a constant current battery charger. Benefits include p= ulse charging for desulfation and the fact that it can charge batteries of = any voltage. Well, with incandescent light bulbs getting scarce and me ...


SSD relay - or how to charge 2 batteries at one time

Started by Sonnich Jensen in sci.electronics.design1 year ago 23 replies

Hi all I have a camper van, at it has to batteries - one for the car itself, and one for axial stuff, such as light, fridge etc for the living...

Hi all I have a camper van, at it has to batteries - one for the car itself, and one for axial stuff, such as light, fridge etc for the living area. By design there is a relay that kicks in when there are enough RPMs to also charge the axial battery. To put it simple - when starting the car, the cars battery get charged immediately, the axial battery only when I start moving. It simple put...


Wireless shoe to bicycle motor power induction

Started by Alan Folmsbee in sci.electronics.design2 years ago

Dear electronics design experts. I now propose a product you can cash in on: An electric bicycle with no battery, just induction coils in...

Dear electronics design experts. I now propose a product you can cash in on: An electric bicycle with no battery, just induction coils in the pedals. The person wears shoes with induction coils running at about 400 hz. A battery back pack or belt will power the bike wirelessly. The battery drives the shoes and magnetic fields jump over to the pedals without wires. This allows fast batte...


Maximum power point tracking using microcontroller

Started by bitrex in sci.electronics.design7 years ago 10 replies

I have a microcontroller project that needs to run at night, and I'd like to use a solar panel to charge an AA NiMH battery during the day to...

I have a microcontroller project that needs to run at night, and I'd like to use a solar panel to charge an AA NiMH battery during the day to power it. The battery will then feed a switching converter to power the project at night. I have seen some maximum power point tracking chips for battery charging, but they're relatively expensive. Since I have some extra pins on the uC availa...


PNP for soft switch and reverse battery protection

Started by Peabody in sci.electronics.design3 years ago 66 replies

I'm working on a small circuit that will be powered by a 9V battery. I would like to combine the functions of a soft power switch and reverse...

I'm working on a small circuit that will be powered by a 9V battery. I would like to combine the functions of a soft power switch and reverse battery protection in a single device. I think the answer may be to use a PNP transistor on the high side, with a base resistor to ground - actually to ground through a physical momentary switch, or indirectly to ground via an NPN transistor cont...