battery life indicator

Started by rome...@gmail.com in sci.electronics.design7 years ago 16 replies

Hi all, I am using a 200Ah battery pack for some purpose. It is not a lead- acid battery. I want to know how much of battery life is remaining...

Hi all, I am using a 200Ah battery pack for some purpose. It is not a lead- acid battery. I want to know how much of battery life is remaining in battery after every usage. How to design a circuit? Please share you ideas. Thanks in advance.


Pinout info, iPaq HX2495 battery

Started by Winston in sci.electronics.design7 years ago

Here is what I *think* I know about this Li-ion battery. Please chime in with additions and / or corrections: Starting from the corner, pins...

Here is what I *think* I know about this Li-ion battery. Please chime in with additions and / or corrections: Starting from the corner, pins 1 and 2 are common and will connect to 'battery +' when the battery is turned on. Pin 3 is a pilot level that can be used to turn the battery on if you pull it low and keep it low. The battery will turn off when you allow this pin to float up, pr...


9V PS

Started by OldGuy in sci.electronics.design4 years ago 17 replies

Looking for the simplest way to this. AC powered 9V wall-wart or 9V battery powering a circuit. 9V battery is alkaline so is not charged by 9V...

Looking for the simplest way to this. AC powered 9V wall-wart or 9V battery powering a circuit. 9V battery is alkaline so is not charged by 9V AC supply. Load is < 50 ma. When AC is on, power from the AC to 9v PS. AC off, power from 9V battery. 9V battery only supplies power when 9V AC is off. The catch: the 9V AC PS output may be lower than the 9V battery or visa versa. So a si


Battery

Started by Jean-Christophe in sci.electronics.design8 years ago 22 replies

Since Q = I*T = C*U then C = I*T/U, now if I*T is the capacity of a battery, a 12V 1Ah battery has C = 300 Farads. What is the physical...

Since Q = I*T = C*U then C = I*T/U, now if I*T is the capacity of a battery, a 12V 1Ah battery has C = 300 Farads. What is the physical interpretation of C in the case of a battery ?


Car battery matching with alternator

Started by cameo in sci.electronics.design3 years ago 44 replies

I wonder what you think about the following problem: A car's battery needs to be replaced but the exact capacity battery is not available,...

I wonder what you think about the following problem: A car's battery needs to be replaced but the exact capacity battery is not available, though smaller or larger ones are. My feeling is that the battery capacity is matched by the manufacturer with the alternator's charging capacity, so the replacement battery should also closely match the OEM battery's capacity. Is my assumption corre...


[solar cell + battery] combination. How does the battery not get damaged ?

Started by rover8898 in sci.electronics.design7 years ago

Hello all, I was wondering how a solar calculator works off the solar cells and the battery (when it is in a low light environment) without...

Hello all, I was wondering how a solar calculator works off the solar cells and the battery (when it is in a low light environment) without damaging the battery when there is excess light. (My casio calculator uses both an 1.5V LR44 alkaline battery and is equipped with solar panels). I imagine that the PV cells generate a voltage that may exceed the battery voltage (since the battery disc...


Unsmoothed car battery charger - is it crap?

Started by Eddie in sci.electronics.design8 years ago 150 replies

My car battery is oversized for the car. The battery is a bit old but usually works fine. The battery is flat (I left the lights on). ...

My car battery is oversized for the car. The battery is a bit old but usually works fine. The battery is flat (I left the lights on). My fancy new modern charger senses a poor battery and only puts in very little charge. I used to use a really old charger to charge this battery successfully. I opened up the old charger and saw it was only a transformer and a big rectifier. Tha...


OT Car Battery Explodes

Started by Gerhard in sci.electronics.design7 years ago 70 replies

Yesterday my wife's Toyota Corolla had a battery moment. When she started the car, after it had been parked it for about two hours, there was...

Yesterday my wife's Toyota Corolla had a battery moment. When she started the car, after it had been parked it for about two hours, there was a loud explosion. The results of the battery's side splitting event can be viewed at ftp://ftp.meraka.csir.co.za/pub/in/Battery_Explode/ The battery centre suggested it was possibly over charged. After I installed the new battery I measured a...


Li Battery

Started by OldGuy in sci.electronics.design2 years ago 18 replies

I got a replacement battery for my laptop. It is a Li-Ion type. 6 cell 4400 mAh 10.8 volt In the package docs it states that I should cycle...

I got a replacement battery for my laptop. It is a Li-Ion type. 6 cell 4400 mAh 10.8 volt In the package docs it states that I should cycle the battery all the way down, recharge it and do this several times to improve its capability. What is happening to the battery doing this? If not done what can I expect in terms of the amount of loss of use? --- news://freenews.netfront....


Is there an app which will stress TEST a cellphone battery?

Started by Ahmed E. Souaiaia in sci.electronics.design3 years ago 50 replies

Is there freeware which will expressly stress test a cellphone battery? There are plenty of battery saver Android apps (e.g., Battery Doctor);...

Is there freeware which will expressly stress test a cellphone battery? There are plenty of battery saver Android apps (e.g., Battery Doctor); but, is there a specific Android battery stress-test application? My Samsung Galaxy SIII will last only about two hours with anything useful running (e.g., GPS) and, with the battery hogs turned off (mostly GPS but WiFi, Bluetooth, etc., are inclu...


How can you power superbright LED from a battery efficiently

Started by karotto in sci.electronics.design8 years ago 21 replies

hi there, I am trying to make a video light for my camcorder powered by its internal battery. No problem, I thought. So I charged the battery...

hi there, I am trying to make a video light for my camcorder powered by its internal battery. No problem, I thought. So I charged the battery and measured 8.4 volts. I strung up about 50 LEDs in a combination series and parallel. I used the right resistors so each series circuit would draw 50mA when the battery is fully charged. Worked great except as the battery drained through using LEDs a...


Charge 12v lead-acid battery via pulse width modulation

Started by Anonymous in sci.electronics.design9 years ago 14 replies

I need to charge the 12 volt engine start battery in my sailboat from the 12 volt house battery in the boat. The house battery is the...

I need to charge the 12 volt engine start battery in my sailboat from the 12 volt house battery in the boat. The house battery is the one connected to the alternator. I can't just parallel the two batteries for charging, since the house battery is a long cable run away from the alternator, and when a heavy charge is going into the house battery(50 amps or so), the voltage that the start batte...


1M ohm resistor across battery terminals - Why?

Started by Chappy in sci.electronics.design7 years ago 24 replies

I have a pocket laser power meter which recently stopped...

I have a pocket laser power meter which recently stopped working. http://www.edmundoptics.com/onlinecatalog/displayproduct.cfm?productid=1403 After disassembling it I discovered that the (non-removable) battery is flat (3.5V battery now pushing only 1.5V). The battery had a 1 M ohm resistor soldered across the terminals. It is a 750maH 3.5V lithium thionyl chloride battery (LTC-7PN). ...


Can powerbanks shorten lithium battery life ?

Started by Andy K in sci.electronics.design12 months ago 36 replies

I have a powerbank that I use to charge my cell phone. 10,400 ma is it's capacity. Output 3.7 V It has 2 outputs. 1.0 and 2.1 amps and...

I have a powerbank that I use to charge my cell phone. 10,400 ma is it's capacity. Output 3.7 V It has 2 outputs. 1.0 and 2.1 amps and I use the 2.1 amp My cell battery is about one yr old. (Replacement for orig battery) After charging the battery, it only lasts about 2 days before going dead. During those 2 days, there was no cell phone usage. Battery capacity is listed as...


While discharging, battery voltage increases?

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

I'm discharging a nickel metal hydride (NiMH) AA battery at 500 milliamps. After the first minute or so it shows 1.05 V. Between then and...

I'm discharging a nickel metal hydride (NiMH) AA battery at 500 milliamps. After the first minute or so it shows 1.05 V. Between then and three hours later, the voltage steadily rises to 1.08 V. Is there something wrong with the battery analyzer, or can battery voltage increase very slightly as the battery discharges? Or maybe I'm reading the analyzer voltage that produces the 500 m...


Lithium Ion Battery and RoHs

Started by Anonymous in sci.electronics.design4 years ago 3 replies

Hi, I am considering using the following battery http://ultralifecorporation.com/be-commercial/products/rechargeable/ubp001/ Its...

Hi, I am considering using the following battery http://ultralifecorporation.com/be-commercial/products/rechargeable/ubp001/ Its not RoHs approved. I heard that Europe does not accept electronics devices if they are not RoHs approved. Does LiIon battery need to be RoHs approved? This battery is UL approved and the company says that they sell this battery in europe. jess


sensor interfacing

Started by Anonymous in sci.electronics.design9 years ago 1 reply

i couldnt find help for making a battery meter to show true voltage of a battery while 1.the battery is being charged and when the load is...

i couldnt find help for making a battery meter to show true voltage of a battery while 1.the battery is being charged and when the load is attached at al times


Battery Charger Design

Started by thorin92 in sci.electronics.design8 years ago 28 replies

Dear group, I am trying to design a battery charger for this...

Dear group, I am trying to design a battery charger for this battery: http://uk.farnell.com/varta/55615605940/battery-pcb-mount-6v-5-v150h/dp/863981 I'm familiar with voltage regulators and current limiting etc. but am unsure what parameters to use? If I simply provide 6v limited to 70mA will this work? Thanks in advance


How could I modify alarm system to be kinder to SLA batteries..

Started by Anonymous User in sci.electronics.design8 years ago 3 replies

Hi, It seems to kill a battery every couple years. Pulled battery today, warm to the touch, 11.3V. If I read the voltage of the wires...

Hi, It seems to kill a battery every couple years. Pulled battery today, warm to the touch, 11.3V. If I read the voltage of the wires going to the battery when disconnected, it reads 13.71V. It has some sort of detection to indicate when the battery is dead, it issued a fault today because of it. I bought a replacement for it today, but I am wondering, is there anything I can ...


Battery simulator and/or meter

Started by Richard Henry in sci.electronics.design9 years ago 3 replies

I am preparing to test a battery-powered device and I am interested in determining its load on the battery. The load is periodic, but...

I am preparing to test a battery-powered device and I am interested in determining its load on the battery. The load is periodic, but not constant, varying from about 11 watts to about 65 watts depending on what it is doing. A web search for battery simulators located the Keithly 2302 and 2306 instruments. Does anyone have esperience with those, or can recommend a similar or better instr...