ZTS Tester Setup for BP-511A Battery Pack

[BleedingEdge]

Upfront, I admit I am an electronics dunce. But I like lights, so I can't be ALL bad

I have the ZTS MBT-1 battery tester and I am wanting to use it to test my Canon BP-511A Battery packs. I am guessing these packs have two 16500's (maybe 17- or 18-500's) Li-ions. The packaging indicates 7.4V and 1390mAh, so obviously these cannot be tested directly on the ZTS. I have no idea why the capacity of this pack is so small.

Is it possible to build a simple circuit that would allow me to test this battery pack on the ZTS? I realize I cannot test the individual batteries, but it would be really useful to be able to test the pack itself.

Thanks!

 

[BleedingEdge]

I *know* there is a CPF'er out there that can say something like, "Heck, just use a 10 ohm 5W resistor, easy as pie!".

 

[Eismagier]

According to this disassembly, there are two 18490 cells inside. Maybe you could open it up and test the cells individually using extensions?

 

[HKJ]

Why not use a voltmeter to test it?

 

[BleedingEdge]

According to this disassembly, there are two 18490 cells inside. Maybe you could open it up and test the cells individually using extensions?

The disassembly destroys the integrity of the battery pack (you cut it open with an exacto knife) and endangers the batteries as well as the fingers.

 

[BleedingEdge]

Why not use a voltmeter to test it?

I believe there are many threads on this forum indicating that voltage is no measure of remaining capacity, which is the whole reason that I bought the ZTS battery tester. If there is a way to test capacity with my Ideal 61-361 multi-meter, I don't know it.

 

[HKJ]

I believe there are many threads on this forum indicating that voltage is no measure of remaining capacity, which is the whole reason that I bought the ZTS battery tester. If there is a way to test capacity with my Ideal 61-361 multi-meter, I don't know it.

Voltage/voltmeter cannot be used to test remaining capacity on primary and NiMH batteries, but works fine on LiIon batteries.

 

[BleedingEdge]

Voltage/voltmeter cannot be used to test remaining capacity on primary and NiMH batteries, but works fine on LiIon batteries.

Wow! I have read that numerous times, and only now has it really sunk in! I guess I just gotta put in the hours
Thanks so much HKJ!

 

[Eismagier]

Voltage/voltmeter cannot be used to test remaining capacity on primary and NiMH batteries, but works fine on LiIon batteries.

But that's only true for the relative capacity, isn't it? I.e. percentage of a full charge. It's no indicator of what remains of its rated capacity on older cells.

 

[HKJ]

But that's only true for the relative capacity, isn't it? I.e. percentage of a full charge. It's no indicator of what remains of its rated capacity on older cells.

Correct, but no simple battery tester can measure that. To do that you need a device that discharges the battery and measures how much current is in the battery, the cheapest solution for that is probably a hobby charger.

 

[BleedingEdge]

I just topped off my two batteries in my Canon charger.
The 10-year old Canon battery pack reads 8.21v, which according to the chart below means about 90% capacity.
The 10-year old knock-off battery pack (Ultra Power?) reads 8.31v, or better than 90% capacity.

I then took 20 pictures with each battery, outdoors (no flash) in raw mode (old camera, only 3MP over 2-3 minutes using a lens with Ultrasonic image stabilization:
The Canon battery reads 8.06v, and
the knock-off battery pack reads 8.22v.

How is it possible these 10-year old Li-ions are still good? Do I need to test them harder?
They are the only batteries I ever purchased for this camera, and I have taken thousands of pictures with them. They have been severely mistreated; left uncharged for years, more than once.

-----------------------

Chart borrowed from another post (not sure how to include url):

Resting voltages (no load connected) are a good indicator of state of charge. These figures are approximate:

4.2V = 100%
4.1V = about 90%
4.0V = about 80%
3.9V = about 60%
3.8V = about 40%
3.7V = about 20%
3.6V = empty
<3.5V = over-discharged

 

[BleedingEdge]

I have just taken another 80 pictures with each battery (for a total of 100 each), pretty much as fast as the camera would allow:
Canon battery pack reads 7.98v, and the
knockoff battery pack reads 8.11v

The Canon battery pack indicates 1100 mAh, the knockoff has no indication of capacity.
There is no indication of where the knockoff battery pack was made.

It seems like these battery packs are still going strong. Has this sort of longevity been noted previously for Li-ion batteries?