Battery Multimeter Testing Question

[makeyourself]

I'd like to test my eGo batteries with a multimeter to make sure they're charging correctly and that they're generally healthy. One of my batteries is an innokin iTaste VV V3. The manual of this battery states (yes, reading instructions is a silly idea I know!):

Connecting to a volt meter without the load required for high voltages can damage the device

My other battery is a Spinner but I also noticed that the Provari's manual effectively says the same thing, because there's barely any resistance without load this can damage the device.

The problem is that unless I'm mistaken it would be verging on the impossible to connect a standard voltmeter with a standard load because access to the battery's positive terminal would be blocked by the atty/clearo/carto. So I preferably I need somebody with at least moderate knowledge in this field to give me some indication of whether these warnings are "we don't want to get sued" type stuff that can be fairly confidently disregarded or whether they do actually have a point.

 

[Nikkel]

............

 

[Ryedan]

Testing the output of a regulated power supply, like a Provari, the iTaste VV, or the Spinner will not give you much information about the battery. The regulation circuit maintains very close to the voltage it is set to deliver no matter what the charge state of the actual battery inside is. With the Provari, you can remove the battery and check its voltage directly. With a non-removable battery, you're stuck.

Voltage output from these power supplies is generally pulse with modulated (PWM) to make the average voltage change. Depending on the frequency of the PWM, it may not meter correctly anyway with a DMM.

Pretty much the only indication of battery health will be normal operation and length of time between charges.

 

[makeyourself]

Thank you for the replies, whilst doing some more research on this I did eventually realise that testing with any type of voltmeter would be effectively pointless due to what you said Ryedan. To me this a significant flaw with eGo style VV batteries. At least with mods like a Provari you can (I think) easily remove the battery and get a true DC reading of its real voltage and also visually inspect it.

I'm still looking into the issue of whether it's a good idea to apply a voltmeter without load just out of interest, I'll post if I find out anymore.

EDIT: Looking into this further, voltmeters do not provide any current of their own and have extremely high internal resistance. This means that basically what happens when a voltmeter is connected to something is that voltage flows across the voltmeter with negligible loss of current and zero loss of voltage from the device being measured. This is from a physics text book I had lying around. I really fail to see how that could damage an ecig device unless I am completely missing some point or other

 

[Ryedan]

Thank you for the replies, whilst doing some more research on this I did eventually realise that testing with any type of voltmeter would be effectively pointless due to what you said Ryedan. To me this a significant flaw with eGo style VV batteries. At least with mods like a Provari you can (I think) easily remove the battery and get a true DC reading of its real voltage and also visually inspect it.

I'm still looking into the issue of whether it's a good idea to apply a voltmeter without load just out of interest, I'll post if I find out anymore.

EDIT: Looking into this further, voltmeters do not provide any current of their own and have extremely high internal resistance. This means that basically what happens when a voltmeter is connected to something is that voltage flows across the voltmeter with negligible loss of current and zero loss of voltage from the device being measured. This is from a physics text book I had lying around. I really fail to see how that could damage an ecig device unless I am completely missing some point or other

I have eGo batteries and a Spinner. I am a bit of a battery geek, but not being able to measure cell voltage from these has never made using them an issue for me. I have put my DMM on them before, mostly out of curiosity and caused no problems. I was careful not to short the battery when I did that. I check the voltage of my mechanical mod cells all the time, but I have no reason to check the eGo class batteries.

My batteries were either set voltage eGos or VV. You may have an issue with a VW setup in that the regulator might see the high resistance and put out maximum power to try to drive the load. That's just my opinion of a possible failure mode though, I have no experience with VW. The issue goes away of course in VV mode.

 

[makeyourself]

I have eGo batteries and a Spinner. I am a bit of a battery geek, but not being able to measure cell voltage from these has never made using them an issue for me. I have put my DMM on them before, mostly out of curiosity and caused no problems. I was careful not to short the battery when I did that. I check the voltage of my mechanical mod cells all the time, but I have no reason to check the eGo class batteries.

My batteries were either set voltage eGos or VV. You may have an issue with a VW setup in that the regulator might see the high resistance and put out maximum power to try to drive the load. That's just my opinion of a possible failure mode though, I have no experience with VW. The issue goes away of course in VV mode.

Yeah quite plausible, the warning in the Provari manual (which is not VW IIRK) actually talks about low resistance so presumably they are in fact talking about a short. I would have thought that either the voltmeter's resistance or just a quick button press would have prevented that but I'm no expert. Maybe I'm being too cautious but I've seen a lot of warnings and the odd horror story about lithium batteries so I thought that checking the charge voltage would be valuable. I know that my mobile phone for instance can read off the charge voltage and give me an indication that the battery is in good health. It would seem to me that knowing whether a battery is in good health is tricky with an eGo which from the limited amount I know could in very rare circumstances be dangerous.

 

[edyle]

I'd like to test my eGo batteries with a multimeter to make sure they're charging correctly and that they're generally healthy. One of my batteries is an Innokin iTaste VV V3. The manual of this battery states (yes, reading instructions is a silly idea I know!):


My other battery is a Spinner but I also noticed that the Provari's manual effectively says the same thing, because there's barely any resistance without load this can damage the device.

The problem is that unless I'm mistaken it would be verging on the impossible to connect a standard voltmeter with a standard load because access to the battery's positive terminal would be blocked by the atty/clearo/carto. So I preferably I need somebody with at least moderate knowledge in this field to give me some indication of whether these warnings are "we don't want to get sued" type stuff that can be fairly confidently disregarded or whether they do actually have a point.

The problem is if every top .... and wendy stuck a multimeter probe down in the 510 threadwell to touch the center positive pin, half of them are probably going to accidentally short out on the 510 threads at the top.

To measure mine, I use an alligator clip jumper to the negative side, and then stick the probe down the center ; you need one hand to hold the probe and the other hand to fire the button briefly to make the measurement.

 

[edyle]

Thank you for the replies, whilst doing some more research on this I did eventually realise that testing with any type of voltmeter would be effectively pointless due to what you said Ryedan. To me this a significant flaw with eGo style VV batteries. At least with mods like a Provari you can (I think) easily remove the battery and get a true DC reading of its real voltage and also visually inspect it.

I'm still looking into the issue of whether it's a good idea to apply a voltmeter without load just out of interest, I'll post if I find out anymore.

EDIT: Looking into this further, voltmeters do not provide any current of their own and have extremely high internal resistance. This means that basically what happens when a voltmeter is connected to something is that voltage flows across the voltmeter with negligible loss of current and zero loss of voltage from the device being measured. This is from a physics text book I had lying around. I really fail to see how that could damage an ecig device unless I am completely missing some point or other

With advanced devices like the provari, vamo svd zmax etc, theres somewhere in the menu you will find the battery voltage (not the regulated output voltage of the whole device)

Example on my vamo, holding down the left button shows the voltage; right now mine reads 3.8 volts; holding down the right button shows ohms; right now it reads 2.4 ohms. My vamo is operating VW at 4.5 watts; changing the watts doens not change the voltage measurement of 3.8 volts which is the measured battery voltage, not the overall output voltage of the device.

 

[atomizer mizer]

Using an adapter in place of the atomizer\cartomizer and wires soldered to the center pin and case of the adapter, a hobby charger could be used on the discharge mode to test the mah rating of the battery. Just use some tape on the power button of the battery and stop discharging at 2.8 or 3.0 volts. To do this safely the battery should probably be discharged at a current rating below it's normal usage. 1amp would probably work.

"....a battery that is rated at 1000 mAh would be completely discharged in one hour with a 1 amp load placed on it. If this same battery had a 500 milliamp load placed on it, it would take 2 hours to drain down....". Using the hobby charger as the load the capacity can be calculated which should show if the battery is in a safe condition. A battery rated at 1100mah but only tests as 400mah would be a prime candidate for the reclamation bin at home depot. Most chargers have a discharge setting for nimh and lipo battery technology.

 

[makeyourself]

Thank you am, I have only just noticed your post, I don't own a hobby charger and I'm not sure I'd go to that length to check battery health but its nice to know how if I do decide to! I have discovered a couple things since my last past:

a) I went ahead and checked the output voltage on my Spinner anyway and it looks like it outputs true DC. The Spinner was set at 3.3V, reading I got was 3.31V and this was not fluctuating whatsoever with multimeter set to DC.

b) The iTaste VV does in fact have the feature that edyle describes, if you press + and - together you get the load resistance followed by the cell voltage. Since I'd owned the battery I'd been trying to work out what this seemingly random voltage being displayed actually was!