guide me on a battery tester

[dragosios]

Any measuring instrument is as good as the user knowledge. It shows a value, but it's up to the humans to understand what this value mean.
As for measurements ... yes, a cheap multimeter is better than nothing. But the difference between a 3% plus some digits of a cheap multimeter and some very expensive ones with 6+ digits can be put to good use when measuring something important, designing things and so on. Such a multimeter is very expensive, it needs warm up time, even cheap cables can make a difference, so this is not something for daily use.
Overall, for somebody with enough knowledge, a cheap multimeter is enough if it works. But cheap multimeters are not so durable, during time they can have different problems even leading to errors, which again can be detected given enough knowledge.
A voltage tester, on the other hand, gives more reliability because is not so complex (when it comes to user interface) and probably even more durable since the error is not huge to be shown anyway. When you have 3-5 LED's as display, a 3% error is unlikely to show frequently..
P.S. A specific resistor in paralel with multimeters input is doing the same thing as a tester, just not as automated. Some analog multimeters have a lower impedance than modern digital ones and can be more accurate.

 

[chillinn]

when measuring something important

I think you're absolutely right, here, I just don't know what that might be where testing a cell as opposed to replacing a cell is more important. I can't say what they're using them for, but a friend of mine gets buckets of hardly used L91 from the surgeon his wife works for, because they replace them every time whatever device is used. I've worked in live reinforcement and before every show replaced the batteries in scores of lavaliere microphones even though nearly all of the cells had enough capacity for the entire three to six week run of the all the shows, but it was important enough not to have a microphone die that I did it, something like $100 in batteries wasted for every week the show ran. I guess the point I'm getting at is the question of when it is more important to accurately test a battery's capacity as opposed to replacing it with a fresh one, and I guess the answer is in those situations where there is no money being made and economy is important. So the focus becomes saving money; criticality is secondary.

 

[dragosios]

I completely agree. batteries are wasted sometimes.
Where I live we have a bin for recycling. If I take a quick look in that bin I find even new batteries or rechargables thrown out because they think are primaries, even 18650 which there is no way to look like a primary.
But in very simple words: a tester is enough to test. If you have some knowledge even that simple few dollars tester can be a very good tool for you. Sure, if you have the money to buy a more expensive one is even better.

 

[electrolyte]

I am not adding much by saying that if you have a bunch of different battery types, you can make your own tester with a breadboard, some resistors and a voltmeter or two (or more likely a multimeter. You may need a specific resistor for each battery type, but that is not a big deal for even a non electronics guy like me. I set up to test a specific type of battery recently and I've never done that before.

I've got a bunch of Zigbee transmitters in a MESH network monitoring lab equipment. The transmitters use lithium thionyl chloride batteries. As part of the monitoring package, battery voltage gets transmitted, but I have never been able to make much use of the data. There are pulses and baselines, but the correlation to battery state seems pretty weak to me. Finally I gave up and after studying the battery data for an appropriate load, ordered a hand-full of a matching resistor. Now if a transmitter starts dropping out, I can take out the batteries and it is easy to say that they are too discharged or are OK.

The LiSOCl2 cells are exceptionally high energy density, wide operating temperature range, and exceptionally low self discharge rate. Trouble is that the energy delivery rate is painfully slow* for a transmitter so they are paired with either a hybrid layer capacitor (in my case) or a Li-ion battery to harvest the power for pulse data transmission.

* Xeno XL-060F is rated for 60 mA continuous and 120 mA for 0.1s every 2 minutes. Tadiran TL-5903 spec sheet says 100 mA/200 mA.

 

[alpg88]

just recently got this one, so far no complaints.

 

[aznsx]

just recently got this one, so far no complaints.

View attachment 45855

That looks pretty cool for a handy quick-check device. Gotta a manufacturer name? I don't see one, which makes me wonder how proud of it they are.

 

[Mr. LED]

@chillinn does this 168Max apply a load to the battery or just measure the resting voltage like a multimeter?

 

[M@elstrom]

I just test the voltage & amp draw on a particular cell, often a cell that appears to hold a respectable voltage fails to hold sufficient amp capacity, this is the methodology I use to identify problem batteries, multimeters aren't expensive but sure are convenient for a range of uses 👍

 

[dragosios]

@chillinn does this 168Max apply a load to the battery or just measure the resting voltage like a multimeter?

Almost all battery testers I encountered are measuring voltage while a resistor is in parallel with the load. Nothing fancy, a good old resistor and the reading is calibrated for that resistor value.
We can simulate this on a poor man version by measuring with the voltmeter in a multimeter while having a resistor in paralel with probes. I used a 3k from a Fluke 225 stray voltage tester and is much better than nothing.
Altough for low voltages like NiCd/NiMh a lower value should be better.

I just test the voltage & amp draw on a particular cell, often a cell that appears to hold a respectable voltage fails to hold sufficient amp capacity, this is the methodology I use to identify problem batteries, multimeters aren't expensive but sure are convenient for a range of uses 👍

Again, a parallel resistor makes wonders here. Anything you have available in the low kiloohms or even ohms for the high current cells. Just make a quick measurement and use common sense (for low ohmic resistors use something with a few watts rating).

 

[orbital]

+

Posting this 'cause it's a terrifico deal (auto ranging)

comes out to only $19

Amazon.com

 

[alpg88]

That looks pretty cool for a handy quick-check device. Gotta a manufacturer name? I don't see one, which makes me wonder how proud of it they are.

Oops, did not see this before, sorry for the late response, there are no other markings on the tester itself, nor blister pack that it came with. however googling bt189 gives you many different testers that similar to this one, you may find more info there.

 

[ABTOMAT]

ZTS doesn't make just one tester. If you don't want the $99 brick they have smaller ones that measure fewer types of cells. I use both. And the earlier guy was right, they don't have a complicated interface. It just looks busy because they have a separate + terminal for each cell type.