How do I check ACTUAL amps on a unmarked battery?

[DogDriver]

Hi,
I have some batteries that came with my headlamps I use for running sled dogs.
They never seem to last very long. ( probably very low MAH) so I got some new ones but they are re-wraps and I was wondering how to check a battery for the ACTUAL amps its putting out? That seems like a good skill to have when using Mech. Mods.
Plus , I want to change out my batteries before they reach 3.1 volts etc left is that correct? Guess that time will vary with each Mod and how its used etc,, what tank, How heavy one vapes etc. Particular batteries will all be different so wish there was some way to KNOW when they are getting low but I guess on a Mech. Mod there is not any way to do that.
Maybe take it out, put it on a Multi meter then either change it or put it back in. Would seem one would get to know that set up after a few checks. That is the only way I can see doing it. Anyone got a better way? Plus that way to check Actual Amps?
Thank you very much all.
Andrea

 

[subwayaznm]

I don't know how to read the Mah of a battery but there is a Forum on here that might help. However when using a Mech Mod you can sense the vapor drop off; which will clue you in that your battery might be getting drained. At which time you can stick the battery into a Regulated Mod, use the multimeter as you stated, or if your battery charger has a read out. Stick the battery on it.
I hope that helps some and check the Battery forum on here. There are some real Gurus there

 

[Baditude]

I was wondering how to check a battery for the ACTUAL amps its putting out?

Unfortunately, there is no easy way for the average consumer to determine the actual amps a battery is putting out. You need sophisticated equipment that the average consumer doesn't have to determine this.

@Mooch is an ECF Member who works in the electronics/battery field, and for the past year has been bench testing 18650, 26650, and 18350 batteries and publishing the results in his blog.

My cell testing equipment and setup
What's done for each cell test?

 

[Robert Cromwell]

Unfortunately, there is no easy way for the average consumer to determine the actual amps a battery is putting out. You need sophisticated equipment that the average consumer doesn't have to determine this.

@Mooch is an ECF Member who works in the electronics/battery field, and for the past year has been bench testing 18650, 26650, and 18350 batteries and publishing the results in his blog.

My cell testing equipment and setup
What's done for each cell test?

THIS!

Also many/most batteries designed for flashlight use are not safe to use in in mods at higher wattages.

 

[DaveP]

The only charger i know of that gives you MAH readings as it charges is the Xtar VC4. It's available at Amazon as low as $22.

The MAH rating of a battery tells you how many milliamps per hour it can provide safely. MAH also indicates the total capacity of the battery. Higher is better. The amp rating tells you the continuous discharge load the battery can take.

Amp rating such as 20A means that it can deliver a maximum 20 amps continuously to a device. If you are a low resistance vaper you need to know the current draw of your device and you have to determine how many amps your device is drawing to choose the right battery for that application. Check out the battery to make sure that it's capable of meeting the specs written on the battery. Mooch has battery tests for most of the popular lithium ion cells used for ecigs.

Most devices that use lithium batteries perform an automatic shutdown at around 3.2v to 3.4v. That's because the farther you discharge a lithium battery the more current it will draw when charging from a discharged state. If you discharge it too low it may not recover.

 

[Canadian_Vaper]

It's kind of a tough thing to do without the right equipment, you basically set up an amp draw, lets say 1 amp and monitor the temperature of the battery, if the temperature stays within a decent range, up the amp draw and monitor at the next level..

From my experience the cheap flashlight batteries "4000-5000-6000" mah usually have a 1-4amp draw and despite their overrated mah ratings are usually between 1200-2000mah...

If you want good flashlight batteries I recommend the panasonic 3400mah ones because they have a large capacity and have enough draw to power high powered LED flashlights like XML-T6/L2 etc etc...

$8.61 Panasonic NCR18650B Rechargeable 3400mAh 3.7V 18650 Li-ion Batteries 2-pack - authentic cells / test capacity 3315mAh / 2-pack at FastTech - Worldwide Free Shipping

Please do no use flashlight batteries for vaping...

 

[Jim_ MDP]

Wait up there Dave...

MAH is the safe level of discharge that a lithium battery can deliver without overstressing and overheating. Of course, you can dead short the terminals and it will deliver all the power it has in a few seconds to a minute. That results in high heat, spewing, and eventual destruction of the cell.

For our purposes... mAh is a measure of the cell's capacity.

The MAH rating of a battery tells you how many milliamps per hour it can provide safely. Higher is better. The amp rating tells you the maximum load the battery can take.

No.
mAh is capacity and the amperage rating CDR (Continuous Discharge Rate) is the capability.

Due to design, and the laws of physics, there's generally a trade off... you can't have both.
Higher mAh is great for vapetime... unless you need higher capability (CDR) for higher wattage.

For example... there's no 30A CDR 3000 mAh 18650 in existence.
You must choose which parameter is more important, or use 20A/2500mAh as a happy medium.
(I don't care for the price premium for a 20A 3000mAh's small extra runtime. YMMV)

Amp rating such as 30A means that it can deliver 30 amps to a device momentarily without damage. What that tells you is that it can power a low resistance atomizer for vaping or another intermittent load at high amperage for short periods of time.

No.
Outside of Samsung releasing the "pulse" ratings for their 25R (they're impressive too), no one else does, so only a true CDR is of use to us.
(And anything above 30A is a re-wrapper's over-spec lie, and a 30A cell will be ~1200-1500 mAh... there's that trade-off)

It (CDR) means the amp draw the cell can sustain, from full charge all the way down (to about 3.2v) without heating to levels that might/would damage the cell or shorten its' useable lifespan.

Most devices that use lithium batteries perform an automatic shutdown at around 3.2v to 3.4v. That's because the farther you discharge a lithium battery the more current it will suck up when charging back up. High current creates heat and heat kills a battery faster than almost anything you can do to it.

No.
A charger will supply what its' circuitry is designed to provide... within the ratings of the power supply. But it is possible to set a selectable rate charger higher than a cell can take.
Pay attention to a charging cell's temp.

I you want to check amperage on a USB device you can use the AboveTek Volt-Amp meter for $12.99.

An in-line ammeter is a cool thing, useful too, but doesn't address the OP's question.

 

[Jim_ MDP]

And I'm still failing to imagine any scenario where I'd put a mystery wrapped battery powered mod up to my face.

My pretty, pretty face.

 

[OhTheAgony]

You drive a dog?

...I think that's illegal in my country...


Sorry, no real advice here, except maybe buy more reliable batteries and ditch those risky .......s?

 

[OhTheAgony]

I would swear I've used that word before...

Oh well

 

[DaveP]

Wait up there Dave...



For our purposes... mAh is a measure of the cell's capacity.
No.
mAh is capacity and the amperage rating CDR (Continuous Discharge Rate) is the capability.

Due to design, and the laws of physics, there's generally a trade off... you can't have both.
Higher mAh is great for vapetime... unless you need higher capability (CDR) for higher wattage.

True, it's the amount of power a battery can deliver over time. A 2000mah battery can deliver 1000ma (1A) for 2 hours or 100ma (.1A) for 20 hours. It's also used as an indicator of how much power is stored in the cell. Higher is generally better. I think of it like a gas tank. If you drive a 4 cylinder you might go several times farther than a V8.

For example... there's no 30A CDR 3000 mAh 18650 in existence.
You must choose which parameter is more important, or use 20A/2500mAh as a happy medium.
(I don't care for the price premium for a 20A 3000mAh's small extra runtime. YMMV)

I used 30A for a reference. I should have used 20A to indicate reality. Yes, Mooch has proven that there's no real 30A battery in his tests.

No.
Outside of Samsung releasing the "pulse" ratings for their 25R (they're impressive too), no one else does, so only a true CDR is of use to us.
(And anything above 30A is a re-wrapper's over-spec lie, and a 30A cell will be ~1200-1500 mAh... there's that trade-off)

It (CDR) means the amp draw the cell can sustain, from full charge all the way down (to about 3.2v) without heating to levels that might/would damage the cell or shorten its' useable lifespan.

Yes, The ratings are CDR instead of max, but they do indicate the maximum safe discharge level. We don't want people to think that's not so.

No.
A charger will supply what its' circuitry is designed to provide... within the ratings of the power supply. But it is possible to set a selectable rate charger higher than a cell can take.
Pay attention to a charging cell's temp.

If you monitor the current drawn by the charger during charge on a deleted cell, it's MUCH higher at the outset than it is when the battery begins to approach full charge. I've proved that with the AboveTEK Voltage/Amperage meter I linked to in my OP. That's true with USB ecigs and cellphones, too. Most of the USB charged devices start out around 800ma and taper down to 100ma or so before declaring charge complete.



An in-line ammeter is a cool thing, useful too, but doesn't address the OP's question.

True, the meter I referenced in the post will monitor the input current to the charger, not the battery itself. The only charger I own that shows actual battery draw in amps during charging is the Xtar VC4.

Replies bolded in blue in the quote above. (click to expand).

 

[Jim_ MDP]

Replies bolded in blue above.

They're still mistaken.

Primarily in that you think the battery is "sucking" in energy, and a misunderstanding the how and the why of a 3-stage charging cycle.
It's controlled by the charger circuitry reading the battery's state, not the battery itself.
And, generally, max-rate selectable.

That applies to what you think the Xtar is displaying as well.

And again... higher mAh is not "generally better" if it means the CDR I require cannot be met. It's a trade-off.

 

[DaveP]

They're still mistaken.

Primarily in that you think the battery is "sucking" in energy, and a misunderstanding the how and the why of a 3-stage charging cycle.
It's controlled by the charger circuitry reading the battery's state, not the battery itself.
And, generally, max-rate selectable.

That applies to what you think the Xtar is displaying as well.

And again... higher mAh is not "generally better" if it means the CDR I require cannot be met. It's a trade-off.

I don't believe the battery is "sucking in energy". Lithium Ion batteries charge in a similar fashion as lead-acid batteries in cars. During charging the ions move from the positive battery pole (which supplies the ions), through the electrolyte, and to the negative graphite pole. The process reverses when it's used to provide power to a device. When all the usable ions migrate back to the positive pole, the battery is "dead" until charged again.

Yes, the charger reads and monitors the battery's charge level and applies a reverse charge while reading the voltage level of the battery. When the charger sense that the voltage has reached a pre-determined cut-off level, charging stops.

Most of the MAH discussion is debatable and dependent on battery build quality. Higher MAH does generally mean more vape time than lower MAH. Higher MAH is also coupled with lower CDR. As you said, you can't have both in one cell and you can't always trust the manufacturer to print the ACTUAL MAH or CDR on the cell and there are good batteries and there are cheap batteries.

Anyway, thanks for critiquing my post. I dashed it off rapidly, finishing up with a lick and a promise to edit later and clarify. At the time, my wife was waiting for me to go down to the beach while I was posting. We are on vacation in Florida this week!

 

[Jim_ MDP]

At the time, my wife was waiting for my to go down to the beach. We are on vacation in Florida this week!

LOL... and you wasted time posting on a forum. You fool !11!!

Enjoy the vacation.

 

[DaveP]

LOL... and you wasted time posting on a forum. You fool !11!!

Enjoy the vacation.

Yep, I can't seem to get my head out of the e-cigarette forum. That's what I get for taking my laptop on vacation.

I'm actually trained in all this stuff. I'm a retired tech rep who spent 38 years chasing down electrical, mechanical, and digital logic related problems in my assigned territory for a world wide company. Of course, back then a lithium ion battery was something that backed up the non-volatile memory where settings were stored on a circuit board. If it failed, you chunked it and install a new NVM battery on the board, just like we do on our computers when the date and time reset to default.

 

[Jim_ MDP]

This should be about the only time of day I'd find Florida tolerable in the summer.

Get back out there!
Go watch cigars being rolled. Can't see that in Georgia (I think).

 

[DaveP]

Hi,
I have some batteries that came with my headlamps I use for running sled dogs.
They never seem to last very long. ( probably very low MAH) so I got some new ones but they are re-wraps and I was wondering how to check a battery for the ACTUAL amps its putting out? That seems like a good skill to have when using Mech. Mods.
Plus , I want to change out my batteries before they reach 3.1 volts etc left is that correct? Guess that time will vary with each Mod and how its used etc,, what tank, How heavy one vapes etc. Particular batteries will all be different so wish there was some way to KNOW when they are getting low but I guess on a Mech. Mod there is not any way to do that.
Maybe take it out, put it on a Multi meter then either change it or put it back in. Would seem one would get to know that set up after a few checks. That is the only way I can see doing it. Anyone got a better way? Plus that way to check Actual Amps?
Thank you very much all.
Andrea

Here's a long list of battery tests done by our local battery expert, Mooch. You can research batteries that you are thinking about buying and verify them before plunking down the cash.
List of Battery Tests | E-Cigarette Forum

 

[Mooch]

I don't believe the battery is "sucking in energy". Lithium Ion batteries charge in a similar fashion as lead-acid batteries in cars. During charging the ions move from the positive battery pole (which supplies the ions), through the electrolyte, and to the negative graphite pole. The process reverses when it's used to provide power to a device. When all the usable ions migrate back to the positive pole, the battery is "dead" until charged again.

Yes, the charger reads and monitors the battery's charge level and applies a reverse charge while reading the voltage level of the battery. When the charger sense that the voltage has reached a pre-determined cut-off level, charging stops.

Most of the MAH discussion is debatable and dependent on battery build quality. Higher MAH does generally mean more vape time than lower MAH. Higher MAH is also coupled with lower CDR. As you said, you can't have both in one cell and you can't always trust the manufacturer to print the ACTUAL MAH or CDR on the cell and there are good batteries and there are cheap batteries.

Anyway, thanks for critiquing my post. I dashed it off rapidly, finishing up with a lick and a promise to edit later and clarify. At the time, my wife was waiting for me to go down to the beach while I was posting. We are on vacation in Florida this week!

PMJI...
Li-ion chargers don't shut off at a certain voltage level. They shut off when the charging current has dropped to a certain level, often 1/10th or 1/20th of the charging current setting. The battery spends a considerable amount of time at or near 4.20V, depending on its internal resistance.

The capacity rating is set by discharging at a specific low current value, typically about 0.5A. Greater capacity always means greater running time at that current level. When vaping we draw significantly more current so the effective capacity is affected by the internal resistance of the battery, which lowers the battery's voltage and affects its running time to varying degrees depending on the battery. This is effectively what you were saying but I did want to mention that capacity ratings are accurate....from Samsung/Sony/LG/Panasonic/Sanyo at least. From other companies, who knows.

Hoping Florida is awesome!

 

[r77r7r]

.

 

[DaveP]

PMJI...
Li-ion chargers don't shut off at a certain voltage level. They shut off when the charging current has dropped to a certain level, often 1/10th or 1/20th of the charging current setting. The battery spends a considerable amount of time at or near 4.20V, depending on its internal resistance.

The capacity rating is set by discharging at a specific low current value, typically about 0.5A. Greater capacity always means greater running time at that current level. When vaping we draw significantly more current so the effective capacity is affected by the internal resistance of the battery, which lowers the battery's voltage and affects its running time to varying degrees depending on the battery. This is effectively what you were saying but I did want to mention that capacity ratings are accurate....from Samsung/Sony/LG/Panasonic/Sanyo at least. From other companies, who knows.

Hoping Florida is awesome!

Thanks for the clarification. I have noticed that when my AboveTEK USB voltage/current monitor is installed inline with a USB charged mod the current load starts out around 800ma and tapers down over the charge duration to less than 100ma before declaring charge complete on the mod.

OTOH, my Efest LUC 4 and my Xtar VC4 blur the apparent process by showing real time battery voltage readings during charge. When the voltage reaches 4.2v it's not long before the charger declares charge complete. I assumed that a combination of both current and voltage were used to determine shutoff.

I need to go back and review charger theory. Thanks again for the explanation.