LT1185-based lead acid battery charger

Started by Piotr Wyderski in sci.electronics.design8 years ago 13 replies

I am designing a prototype charger of a lead-acid battery used as a backup power supply source. The input voltage is synchronously rectified...

I am designing a prototype charger of a lead-acid battery used as a backup power supply source. The input voltage is synchronously rectified 12VAC and the current is


Cordless corded tools?

Started by John Doe in sci.electronics.design10 years ago 21 replies

I just converted a Dremel 10.8 V rotary tool to use Bosch 10.8 V batteries. I always have the rotary tool immediately in front of me, so the...

I just converted a Dremel 10.8 V rotary tool to use Bosch 10.8 V batteries. I always have the rotary tool immediately in front of me, so the battery will either be worn on a neck strap or be set down near the work. The wires coming from the rotary tool plug into the battery, using a socket taken from another Bosch tool. That was done because the rotary tool battery charger sucks. App...


Coloumb counting

Started by bitrex in sci.electronics.design4 years ago 8 replies

Anyone implemented a coloumb counting algorithm on a uP before for estimating LiPo battery SOC? I'm powering an 8 bit AVR and a few external...

Anyone implemented a coloumb counting algorithm on a uP before for estimating LiPo battery SOC? I'm powering an 8 bit AVR and a few external widgets off a small 3.7 volt single-cell LiPo battery, about the size of a stick of gum, and would like to give it a rough estimate of the battery's SOC without using more hardware. I have at least one 10 bit ADC channel available for sensing. Fo...


Tesla Battery Fantasy Time...

Started by Jim Thompson in sci.electronics.design4 years ago 23 replies

Tesla Battery Fantasy Time... ...Jim Thompson -- | James E.Thompson ...

Tesla Battery Fantasy Time... ...Jim Thompson -- | James E.Thompson | mens | | Analog Innovations | et | | Analog/Mixed-Signal ASIC's and Discrete Syst


Identify the connections on a cordless tool battery

Started by Anonymous in sci.electronics.design2 years ago 1 reply

Im trying to Identify the connections on a cordless tool battery. Not for any real reason, just curious why so many contacts are needed. Its a...

Im trying to Identify the connections on a cordless tool battery. Not for any real reason, just curious why so many contacts are needed. Its a 18v Hitachi battery from a cordless drill. Batt # BCL 1815 There are 7 contacts. One is not used. The 6 which are used are labeled as such. 1. + 2. - 3. T 4. LS 5. LE 6. L+ The + and - are obvious. But what are the others for?


Re: What's the short circuit current of a 9V battery?

Started by David Eather in sci.electronics.design4 years ago

On Mon, 19 Jun 2017 01:22:43 +1000, wrote: get hold of the highest resolution multimeter you can - it also helps if it is accurate but...

On Mon, 19 Jun 2017 01:22:43 +1000, wrote: get hold of the highest resolution multimeter you can - it also helps if it is accurate but resolution is more important in this case. measure the open circuit voltage of the battery call it V1 place a 330 ohm resistor across the battery. call it R There is nothing magical about 330 ohm - just that a 1/4 watt re


Why is DeWalt's new battery so big?

Started by John Doe in sci.electronics.design3 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.design5 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.design8 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.design6 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.design8 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.design3 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.design4 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.design10 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.design9 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.design3 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.design4 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.design3 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.design9 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.design10 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 ? ...