How to make battery discharge graphs?

[5kids]

Like most people on CPF, I've got loads of rechargeable batteries of unknown condition or capacity. I solved my AA NIMH battery testing by buying a MAHA 9000 charger tester that I really like. I need to know the capacity of my LiON 3.6V 10440, 14500 & 18650 cells and more important my 7.2V camera batteries.

I understand well how to use a DMM and read the nice tutorial on that,
http://www.candlepowerforums.com/vb/showthread.php?t=236906
but as you all know a voltage measurement does not truely indicate capacity, it must be measured by a discharging a load over time. I don't want to build my own circuit for this and am willing to spend $75-100.

I'd like to be able to make these types of graphs as shown in this post:
http://www.candlepowerforums.com/vb/showthread.php?t=234724&highlight=capacity+discharge

If the graphs are too difficult or expensive, than a simple mAH capacity is sufficient, I just can't be in the middle of a photo shoot and find out I've got a bad rechargeable camera battery. Its not practical to just replace camera batteries because of age, as some fail earlier than others. I don't need charging capability from the discharger and would like to be able to select the cut-out voltage for a 3.6v or 7.2v cells/batteries to prevent over discharge since my 14500 & 18650 are protected and the camera batteries and 10440's are un-protected. I do have limited soldering capabilities, I just don't want to be designing or building my own circuit board.

 

[ptolemy]

Like most people on CPF, I've got loads of rechargeable batteries of unknown condition or capacity. I solved my AA NIMH battery testing by buying a MAHA 9000 charger tester that I really like. I need to know the capacity of my LiON 3.6V 10440, 14500 & 18650 cells and more important my 7.2V camera batteries.

I understand well how to use a DMM and read the nice tutorial on that,
http://www.candlepowerforums.com/vb/showthread.php?t=236906
but as you all know a voltage measurement does not truely indicate capacity, it must be measured by a discharging a load over time. I don't want to build my own circuit for this and am willing to spend $75-100.

I'd like to be able to make these types of graphs as shown in this post:
http://www.candlepowerforums.com/vb/showthread.php?t=234724&highlight=capacity+discharge

If the graphs are too difficult or expensive, than a simple mAH capacity is sufficient, I just can't be in the middle of a photo shoot and find out I've got a bad rechargeable camera battery. Its not practical to just replace camera batteries because of age, as some fail earlier than others. I don't need charging capability from the discharger and would like to be able to select the cut-out voltage for a 3.6v or 7.2v cells/batteries to prevent over discharge since my 14500 & 18650 are protected and the camera batteries and 10440's are un-protected. I do have limited soldering capabilities, I just don't want to be designing or building my own circuit board.

u need CBA II or III for that. its software does the graphs

 

[clintb]

u need CBA II or III for that. its software does the graphs

Or any hobby charger with discharge capability, and has computer interface, such as USB.

There is no doubt the CBA is a very nice piece of gear, but is also overkill for most folks, and is a one trick pony. A hobby charger would provide much more overall value.

 

[ptolemy]

Or any hobby charger with discharge capability, and has computer interface, such as USB.

There is no doubt the CBA is a very nice piece of gear, but is also overkill for most folks, and is a one trick pony. A hobby charger would provide much more overall value.

u are right. but i wasn;t aware of any charger that has that

especially for li-ions

 

[clintb]

u are right. but i wasn;t aware of any charger that has that

especially for li-ions

Heck, most current hobby chargers have a USB interface. These days, I wouldn't even consider one that couldn't interface with a computer and give me some graphs.

 

[Light Sabre]

Get a Radio Shack Cat No. 22-812 DMM, it has a RS-232 output. You can get USB to RS-232 adapters, have a couple and they work great. It will only work with their Meter View program, but will do exactly what you want. Graph the data and at the end of the test you can save the data as an ASCII text file and then import that into Excell if you want. You can screen capture the graph or print it out. Meter View will record anything that the meter can measure. The meter with all necessary accessories, cables, etc and software is only $70. Works great for me and is very inexpenisve. The meter doesn't have an AC adapter, but runs on a 9V battery, but will run 2 weeks straight on an Energizer 9v. The meter is also a battery vampire and will run the 9V down to 5V or less before it quits. The other logging meter I looked at was twice the price with all the same fixings.

 

[smopoim86]

Get a Radio Shack Cat No. 22-812 DMM, it has a RS-232 output. You can get USB to RS-232 adapters, have a couple and they work great. It will only work with their Meter View program, but will do exactly what you want. Graph the data and at the end of the test you can save the data as an ASCII text file and then import that into Excell if you want. You can screen capture the graph or print it out. Meter View will record anything that the meter can measure. The meter with all necessary accessories, cables, etc and software is only $70. Works great for me and is very inexpenisve. The meter doesn't have an AC adapter, but runs on a 9V battery, but will run 2 weeks straight on an Energizer 9v. The meter is also a battery vampire and will run the 9V down to 5V or less before it quits. The other logging meter I looked at was twice the price with all the same fixings.

The hobby chargers with usb do not const much more than that and you get more for your money IMHO.

 

[5kids]

Thanks, I'll look for a hobby charger with USB. I'd really like the UBA, but the finance department (Wife) would notice such a nice new toy. What I should do I sell my other charger that were great for there time, but have been surpassed and don't do single cell charging.

Anyone need a Hobbico Accu-charger or a Maha C777?

 

[5kids]

I like the Hobby Charger route and found a couple that look nice and fit my price range, but I can't find any online owners manual or software demos. The nice thing about the Hobby Charger with USB interface, is that they'll charge and do multiple cycles, and the CBA will only discharge.
anyone have any experience with the Tenergy TB6
http://www.all-battery.com/tenergytb6balancingchargerfornimhnicdli-poli-fesla-1.aspx

or the iCharger 106B? They both look very simlar and could very well be from the same manufactuer.

http://www.hobbycity.com/hobbycity/...me=iCharger_106B-plus_250W_6s_Balance/Charger

 

[clintb]

iCharger 106b+ is a wicked good value. I have two of the iCharger 208B and love 'em.

Another good value is the Bantam BC-8 from Neu Motors for $99. http://www.neumotors.com/store/page10/page10.html

 

[5kids]

I'm looking now at the Thundar T6 which is capable of PC USB interface for only $55!

http://www.hobbypartz.com/thac6smbachw.html

The hobby charger is very appealing because it will function without a PC and can charge and selectively discharge to determine capacity.

My question now is regarding Lithium chemistries. Most of these hobby chargers are compatible with LiPo, LiLo and LiFe lithium batteries, but no mention of Li-Ion. I have typical cylindrical Li-Ion cells from AW, Ultrafire, Trustfire and various camera [Canon (BP-511) and olympus (LI-50B)] and cell phone batteries that I'd like to test. Will these hobby chargers that are listed for LiPo, LiLo and LiFe lithium batteries work with Li-Ion?

 

[Cavelightchris]

I took some graphs that SilverFox made and opened them up in photoshop, properly resized them all to fit over each other, and I made this graph:

But it took me 2 hours, but o well I don't have any cool gadgets like you guys.


Chris

 

[clintb]

My question now is regarding Lithium chemistries. Most of these hobby chargers are compatible with LiPo, LiLo and LiFe lithium batteries, but no mention of Li-Ion. I have typical cylindrical Li-Ion cells from AW, Ultrafire, Trustfire and various camera [Canon (BP-511) and olympus (LI-50B)] and cell phone batteries that I'd like to test. Will these hobby chargers that are listed for LiPo, LiLo and LiFe lithium batteries work with Li-Ion?

To be 100% technically correct, you'd use the LiLo setting, which is the same as Li-Ion, BUT, and here's the goofy thing, most of the Li-Ion cells you have can be charged with either setting. LiLo: 4.10V charge termination. LiPo: 4.20V charge termination. The discharge cutoff Voltage may vary as well.

In a general sense, both LiPo and LiLo use the same type of charging algorithm (CC/CV), they just use different termination Voltage, as stated above.

If the cell specifically states it's 3.6V per cell, stick with LiLo to play it safe. If it's 3.7V per cell, LiPo will be just fine.

Regarding your hobby charger purchase.
- Jun-si is the iCharger manufacturer. They do not make the Tenergy line.
- Purchase iCharger from ProgressiveRC in the U.S.
- Go here for more information you'd care to read about the iCharger line. Manual is in the first post.

Lastly, any reviews you read which state there's no USB, or the firmware has to be updated in some special way is/are referring to the non-plus (106b, 1010b) versions of the charger. Those are long gone and only the plus versions (106b+, 1010b+) are left. Rest assured, if you purchase from either Hobby City, or Progressive RC, you will receive the + version.