How to test aa batteries

how to test aa batteries

Subscribe to RSS

Jul 21,  · A simple method to test any alkaline battery in seconds! Works on AA, AAA, C, D batteries. Jul 11,  · The proper voltage for AA/AAA NiCd/NiMh rechargeable battery is Volts To test the battery, turn on your voltmeter, put the voltmeter on DCV and make sure that it is far above the battery voltage, on most voltmeters there is a setting "20" in the DCV area, so switch your voltmeter .

If we don't know how to batterids a battery we might throw out a perfectly fine battery especially when we have a pile of them somewhere in the drawer. Disclaimer : some people might say that a battery should always be tested under load but I have found that in most common household applications this is insignificant and will not change the results of the testing too much. Notice batteris voltage reading on the voltmeter. If the reading is more than 1.

Otherwise, properly discard of the battery. Tip : do not use old and new batteries in the same device at how many weight watchers points plus calculator same time. Try to use batteries that have same amount of energy stored in them. Another tip: I sort my batteries according to Voltages, 1. I will attach some pictures of measurements in action. Just be very careful of your how to make a snowflakes using paper application.

Reply 8 months ago. I don't mean to insult your intelligence, and if you know your stuff and are certain about what happened, please forgive me. But in case as not too familiar with HVAC and are just guessing, I want to give you a heads-up that the problem could be something else and you may how to test aa batteries to be on the lookout.

Although it appeared a "low battery" was your problem, it could be that the fresh battery, or the some aspect of the battery change just masked or reset a different problem.

I am not an HVAC pro or guru; my observations are not definitive. Prelude over. There are two things that seem unusual to me, and here's what I can tell you.

The thermostat's power just has to decide to close a little circuit on its board, which doesn't usually take much juice. Granted, that doesn't prove anything. The thing that bugs me more is thatit's usually a closed circuit that turns a unit on. Lack of power should result in a unit that fails to turn on.

I won't pretend that I can tell you what else could have been at fault for the "stuck on" condition, or even that I know for certain it wasn't just as you said. I just wanted to help out by ttest you that from here it looks like there might be another problem lurking. If you know something I don't, I'd be happy to have you educate me. Thanks, or you're welcome. Or both. Reply 5 months ago. I have also experienced a brand name thermostat with low batteries that caused my furnace to fault in the on state on two occasions.

The manufacturer heard from me, and they admitted to a problem and sent me a new model of thermostat. I was surprised too!

I think it was a 3M thermostat Question 1 year ago on Introduction. I think it is bagteries oft repeated, unsubstantiated tidbit that is as helpful as the tip, wait 30 minutes after yow before swimming.

I've had to use old and new on countless occasions and regularly eat a whole turkey before during and after my swim and have yet to see any detrimental effects if you can overlook an abundance of glow in the dark turkey farts. Answer 1 year ago. Again no big deal. If the voltages are to different then you'll drive a reverse current through the week battery and it could fail physically.

It's pretty unlikely but not worth the risk. Reply 7 months ago. I quit literally had a battery explode inches from my face a few days ago. Thankfully the battteries acid stayed contained and I wasn't injured. Could it have been the 2 brand new batteries I put in with the 2 very old batteries? Like most, I've heard not to mix old and new but didn't think about it possibly causing batteries to burst. What I found most odd about the batteeies experience was that the light in which the batteries were installed stayed on for a good min after the battery explode.

In fact, I had to turn the light off. Anyone know if that's normal? Question 2 years ago on Introduction. The other day i needed to check the voltage in a couple of AA batteries. I plugged the cables into my analog multimeter and touched the leads to the ends of the batteries and measured the voltage.

When i finished i was putting everything back in the box and noticed i had forgotten to put the batteries in the multimeter but it still worked. Doesn't the meter need batteries to check voltage? Analog meters use power from the battery being tested to swing the needle. Digital testers require an internal battery to work. I believe the battery in a multi meter are necessary for ohm function. It sends a small current through the circuit to measure resistance. Also necessary for continuity checks.

With the multimeter in the photo you can test unloaded and loaded. The battery test loaded position is at the upper right on the dial in the position. Set to this, put the red lead in the middle hole and the black in the bottom. You should read 4. Reply 1 year ago. To those who stumble upon this, this is why you batterirs to test the battery under load. The voltage of an unloaded battery will not change significantly as it dies. A fresh battery and a dead one will both show similar voltages unloaded.

Reply 5 years ago. I think he is talking about testing for voltage while the battery is under load. You're talking about amperage--two different things.

I'd like to offer a few corrections, additions, and pointers. In other words Let's take the example of a AA battery This means that batteriws you were running a toy that drew about mA So how do you check the how to dicipline a 1 year old Under a load.

Let's use the example above But instead We can take the voltage 1. So if we find an 8 ohm resistor and put it across the battery Another issue with the 1. And I believe a batteried is like 1. I actually use this fact in my projects I hope that helps. Reply 5 years ago on Introduction. Also, the test is for determining whether the cell was depleted or not, not whether it had malfunctioned.

If the cell tests fresh under no load, but drops below 1. Reply 3 years ago. I know this comment is 6 months old, but I am going to reply any way in case someone reads this later. As askjerry indicated, testing a battery of any chemistry unloaded is pretty much a useless endeavor. The ONLY way to test a battery is to estimate the current draw scenario, and mA is a good battrries case scenario, and test it with an equivalent load. When you test a battery unloaded you can get nearly the full "new" voltage on a battery with very little capacity left.

Hi, is the resistance going to make any difference during the test? For example I have how to test aa batteries 50 ohms laying around, which should draw a much less current, will it show different result from 8 ohms?

To the point Does testing the battery under load really matter? No, not for most electronic devices. It might matter a little bit if it runs a motor, or perhaps a flashlight. Still, we teest talking about deciding whether to dispose of an inexpensive battery or to replace it with a new one. I see no need to overthink this and go searching for load resistors.

If in doubt-throw it out! Reply 4 years ago.

5 People Made This Project!

Sep 04,  · Sure, you could find or buy a battery tester. But electrical engineer Lee Hite has an easier test: Just drop your nonrecharable AA battery — . Test the battery under load after charging. For AA and AAA, use a resistor of about 10 ohms, or a small incandescent flashlight bulb, in parallel with the multimeter. NiCd or NiMH cells should be ~ volts, though different cell chemistries may give a range of ~ to ~ V. 1. Load the battery with about 6 ohm resistor (that will load the batter by somewhat mA, somewhat like a bike light would draw.). Connect the resistor in parallel to the multimeter. The multimeter should show the voltage enough for a typical device to operate (most of them stop working at around V or about).

Electrical Engineering Stack Exchange is a question and answer site for electronics and electrical engineering professionals, students, and enthusiasts. It only takes a minute to sign up. Connect and share knowledge within a single location that is structured and easy to search. I have a bag of about 50 non-rechargeable AA batteries 1. I bought a multimeter recently and would like to know the best way to test these batteries to determine which ones I should keep and which I should toss. Sometimes a battery will be useless for certain high-power devices e.

Ideally, I'd like to divide the batteries into several arbitrary categories:. Should I be measuring voltage, current, power or a combination of several of these?

Is there a simple metric I can use to determine what to keep and what to toss? While this question relates to non-rechargeable AA cells it is possible that someone may seek to extend the advice to testing other small cells. Shorting Lithium Ion cells as is test 2 is liable to be a very bad idea indeed. This level of discharge can cause injury and worst case may destroy the call, in some uncommon cases with substantial release of energy in the form of flame and hot material.

Generally speaking, if a battery is more than 1 year old then only Alkaline batteries are worth keeping. Shelf life of non-Alkaline can be some years but they deteriorate badly with time. Modern Alkaline have got awesome - still a majority of charge at 3 to 5 years. Heft battery in hand. Learn to get the feel of what a "real" AA cell weighs. Anything under 25g is suspect.

Under 20g is junk. Under 15g is not unknown. Set multimeter to high current range 10A or 20A usually. Needs both dial setting and probe socket change in most meters. If battery has any light surface corrosion scratch a clean bright spot with probe tip.

If it has more than surface corrosion consider binning it. Some only Alkaline cells leak electrolyte over time, which is damaging of gear and annoying at least to skin. Press negative probe against battery base. Move slightly to make scratching contact. Press firmly. DO NOT slip so probe jumps off battery and punctures your other hand.

Not advised. Ask me how I know. Press positive probe onto top of battery. Hold for maybe 1 second. Perhaps 2. Experience will show what is needed. This is thrashing the battery, decreasing its life and making it sad. Try not to do this often or for very long. Lightly used AA or ones which have had bursts of heavy use and then recovered will typically give a few amps.

Non Alkaline will usually be lower. I buy ONLY Alkaline primary cells as other "quality" cells are usually not vastly cheaper but are of much lower capacity. Current will fall with time. Very good cell will fall little over 1 to maybe 2 seconds. More used cells will start lower and fall faster. Well used cells may plummet. I place cells in approximate order of current after testing. The top ones can be grouped and wrapped with a rubber band. The excessively keen may mark the current given on the cell with a marker.

Absolute current is not the point - it serves as a measure of usefulness. After that it's all downhill. A 1V OC cell is dodo dead. Do this a few times and you will get a feel for it. Use a heavyish load and measure voltage. Keep a standard resistor for this. A twisted connection has too much variability. Yes, it is. As well as returning a few batteries to the fold and making your life more exciting when some fail to perform, it teaches you a new skill that can be helpful in understanding how batteries behave in real life and the possible effect on equipment.

The more you know the more you get to know and this is one more tool along the path towards knowing everything Some meters have a battery test mode - a voltmeter with a load in parallel. One of mine a wavetek meterman does. Using this mode you can push down to around 1.

To be honest the the easier approach is: take battery out of demanding device, put in box to be used in undemanding device. It's not just about current but about input voltage - a cheap weather station I have gets fussy below about 2x1. I always use the "brutal" method from Russell's answer.

It's most precise because it also tells you the "fitness" of the battery, not only voltage or short-term power. Used are about A. If they are A, you can still use them in remote controls or digital alarm clocks for years.

Anything below 2 is most likely dead. Works also for rechargeable batteries but they might get damaged over the time. Testing the voltage never worked for me though. Load the battery with about 6 ohm resistor that will load the batter by somewhat mA, somewhat like a bike light would draw. Connect the resistor in parallel to the multimeter.

The multimeter should show the voltage enough for a typical device to operate most of them stop working at around 1. You can wait for a few seconds to be sure. Such battery can power the device beyond doubt so why to throw it away?

If you must be always sure, take a spare new batter with you. I like Russell's 4 answer. What we think of as dead batteries are really batteries with internal resistance built up to limit the available voltage and power.

Russell's 2 answer is a direct method of testing internal resistance. By shorting the terminals and measuring the current, you are really measuring internal resistance because the shorted current is proportional to the internal resistance.

But 4 is better. You are measuring the voltage drop across a resistor, which approximates the way that the battery will be used. The higher the internal resistance, the lower the voltage drop across the external resistor. I use my batteries twice. I use them first in the camera, which draws a lot of current, and needs fresh batteries. Then I use the batteries in my little transistor radio, which draws very little current and can still use batteries with high internal resistance.

Sign up to join this community. The best answers are voted up and rise to the top. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Learn more. How should I use a multimeter to determine which AA batteries to keep and which to toss? Ask Question. Asked 6 years, 8 months ago. Active 11 months ago. Viewed k times. Ideally, I'd like to divide the batteries into several arbitrary categories: As-new condition suitable for most devices Suitable for low-powered devices such as remote controls Not worth keeping Should I be measuring voltage, current, power or a combination of several of these?

Improve this question. Aug 20 '14 at I am still laughing.

2 thoughts on “How to test aa batteries

Add a comment

Your email will not be published. Required fields are marked *