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LP-E6 batteries tests and thoughts

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  • LP-E6 batteries tests and thoughts

    BM cameras consume a lot of power (BMMCC 8W max, Pocket4K 22W max), so tiny LP-E6 battery works in extreme conditions and battery manufacturers wattage measurement usually don't match to real life. Another factor is that BM cameras turns off very early, when battery voltage drops only somewhere to 6.3V, but i don't measure exact min. real life voltage limit yet. In this situation lower capacity cells but with less voltage drop at start works better than higher capacity cells but with more voltage drop at start.
    So here are some of my personal LP-E6 battery tests. My electronic load device is very basic and can't draw charts automatically, so i draw a very simplified charts manually. Note that i compare old batteries (used 2-3 years) to almost new batteries (used 5-6 months), so it may be not too scientific test. I just wanted to see if it worth to move to rather cheap BATMAX LP-E6 batteries, who advertises quality SANYO cells inside.



    BATMAX battery. Marked as 7.2V 1865mAh 14Wh. (New battery. Manufacturer advertises quality SANYO cells inside)
    Fully charged, no loaded - 8.2V
    Measurements under the load 2A (about 13-14W):
    05 min - voltage drops to 6.9V
    09 min - voltage drops to 6.8V
    19 min - voltage drops to 6.7V
    24 min - voltage drops to 6.6V
    29 min - voltage drops to 6.5V
    34 min - voltage drops to 6.4V
    36 min - voltage drops to 6.3V
    38 min - voltage drops to 6.2V
    39 min - voltage drops to 6.1V
    40 min - voltage drops to 6V (8.8 Wh measured capacity)
    Battery turns off when voltage drops under 6V

    Watson LP-E6 battery №1. Marked as 7.4V 2000mAh 14.8Wh. (Used battery. Unknown orange cells inside)
    Fully charged, no loaded - 8.3V
    Measurements under the load 2A (about 13-14W):
    05 min - voltage drops to 6.7V
    16 min - voltage drops to 6.6V
    19 min - voltage drops to 6.5V
    30 min - voltage drops to 6.4V
    36 min - voltage drops to 6.3V
    39 min - voltage drops to 6.2V
    45 min - voltage drops to 6.1V
    46 min - voltage drops to 6V (9.9Wh measured capacity)
    Battery turns off when voltage drops under 5V

    Watson LP-E6 battery №2. Marked as 7.4V 2000mAh 14.8Wh. (Used battery. Unknown orange cells inside)
    Fully charged, no loaded - 8.35V
    Measurements under the load 2A (about 13-14W):
    05 min - voltage drops to 6.4V
    19 min - voltage drops to 6.3V
    26 min - voltage drops to 6.2V
    39 min - voltage drops to 6.1V
    42 min - voltage drops to 6V (9.4Wh measured capacity)
    Battery turns off when voltage drops under 5V

    Original BMMCC battery №1. Marked as 7.4V 2000mAh 14.8Wh. (Used battery. Unknown orange cells inside)
    Fully charged, no loaded - 8.3V
    Measurements under the load 2A (about 13-14W):
    05 min - voltage drops to 6.5V
    18 min - voltage drops to 6.4V
    21 min - voltage drops to 6.3V
    24 min - voltage drops to 6.2V
    33 min - voltage drops to 6.1V
    36 min - voltage drops to 6V (7.6Wh measured capacity)
    Battery turns off when voltage drops under 5V

    Original BMMCC battery №2. Marked as 7.4V 2000mAh 14.8Wh. (Used battery. Unknown orange cells inside)
    Fully charged, no loaded - 8.3V
    Measurements under the load 2A (about 13-14W):
    05 min - voltage drops to 6.5V
    24 min - voltage drops to 6.4V
    32 min - voltage drops to 6.3V
    37 min - voltage drops to 6.2V
    44 min - voltage drops to 6.1V
    46 min - voltage drops to 6V (9.7Wh measured capacity)
    Battery turns off when voltage drops under 5V
    Last edited by shijan; 10-12-2019, 05:00 PM.
    All my custom made accessories for BMMCC/BMMSC now available here https://lavky.com/radioproektor/

  • #2
    Interesting. Just to be sure: how are you applying the load?
    My YouTube channel

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    • #3
      I use no-name 150W electronic load shown on picture. It allow to set constant current (i usually use 2A for capacity tests) and automatically calculate Watt-hours during discharge. In most cases i use it to test my assembled battery enclosures under high load to make sure they work as should. That image was taken from test of battery enclosure with 4x18650 cells.
      For battery testing and automatic charts drawings you need electronic load that connects to PC. Probably ZKE makes the most affordable ones. Something like 200W EBD-A20H costs $100-$150. They also have tiny $20-$30 boards EBD-USB+ and EBD-M05 Mini which are enough to test small batteries with load up to 20V@30W. There are also a lot of more professional brands but prices are too high for hobby usage.



      here is the list of ZKE models:

      Last edited by shijan; 10-13-2019, 07:01 PM.
      All my custom made accessories for BMMCC/BMMSC now available here https://lavky.com/radioproektor/

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      • #4


        Last edited by shijan; 10-13-2019, 06:33 PM.
        All my custom made accessories for BMMCC/BMMSC now available here https://lavky.com/radioproektor/

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        • #5
          Thanks. I was asking just to see if I could add data on my RAVpower batteries, but it clearly wouldn’t be comparable.
          My YouTube channel

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          • #6
            I am also still can't understand what is the the most correct way to test batteries to mimic real life camera behavior?
            My simple electronic load allow only set constant current. So when i set current to 2A, wattage varies a lot depending of battery voltage output.
            More advanced ZKE electronic loads allow to set constant Wattage, and so current will varies depending of voltage drop.
            In real life these two methods may produce very different results.
            All my custom made accessories for BMMCC/BMMSC now available here https://lavky.com/radioproektor/

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            • #7
              Originally posted by shijan View Post
              I am also still can't understand what is the the most correct way to test batteries to mimic real life camera behavior?
              .
              IMHO the most "real life" way is to put it in a camera and start recording.
              Blog: http://frankglencairn.wordpress.com/

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              • #8
                Yes, but camera can't draw discharge charts.
                So i am end up with ordering EBD-M05 Mini. It may looks limited because only have Constant Current discharge mode, but it is tiny sized, it use normal USB cable to communicate with computer instead of rare USB to TTL adapter cables on larger models, and 30W is enough to emulate any camera or monitor power consumption. It will let me know what is going on inside batteries.
                All my custom made accessories for BMMCC/BMMSC now available here https://lavky.com/radioproektor/

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                • #9
                  Good stuff, shijan, thanks. Although, all this confirms for me is that LP-E6 is a horrible battery system for the Pocket cam :P

                  It is still extremely rare for me to get more than 30-40 minutes from a "fully charged" battery. Similar to your testing, the voltage always drops dramatically at the beginning, then levels out, then is in the "maybe I'll turn off soon" zone when close to 6v.

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                  • #10
                    If I'm remembering correctly, that is a typical characteristic of Li-Ion batteries. They drop off sharply from max voltage and then stay relatively consistent at a mid-range voltage before being depleted. Other battery types linearly decrease over time.

                    You can see this if you've ever used electronics where the speed is relative to voltage with AA batteries, and the speed gradually decreases as the batteries deplete, vs something like a LiIon device that stays the same until it dies.

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                    • #11
                      Originally posted by shijan View Post
                      Yes, but camera can't draw discharge charts.
                      .
                      I know, but what are those charts for?
                      The only thing that matters for us is, how long before the camera turns of?
                      Blog: http://frankglencairn.wordpress.com/

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                      • #12
                        Those charts help to predict when it is time to replace a battery. They are allow look into the future. This helps to avoid situation when it seems that battery works ok with camera, but in next day in critical moment it turns off camera after 10 minutes. For example weakest battery in that chart (original BMMCC battery) was usable but very unstable last times. Sometimes it worked well, but sometimes it randomly turned off very quick. If i have those charts measurements earlier, i'll be able to see that this battery became closer to end limit and needs to be replaced or at least used only as backup battery for monitor, but not for camera.
                        All my custom made accessories for BMMCC/BMMSC now available here https://lavky.com/radioproektor/

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                        • #13
                          Originally posted by GeranSimpson View Post
                          If I'm remembering correctly, that is a typical characteristic of Li-Ion batteries. They drop off sharply from max voltage and then stay relatively consistent at a mid-range voltage before being depleted. Other battery types linearly decrease over time.

                          You can see this if you've ever used electronics where the speed is relative to voltage with AA batteries, and the speed gradually decreases as the batteries deplete, vs something like a LiIon device that stays the same until it dies.
                          Yes, all batteries drop voltage under the load. Battery capacity vs applied load ratio makes that start drop more or less dramatic. Larger batteries with lower load will drop less voltage from start. Probably it depends of battery chemistry type as well.
                          All my custom made accessories for BMMCC/BMMSC now available here https://lavky.com/radioproektor/

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                          • #14
                            The best way to get good battery life out of a BM camera is to sell it and get a Canon.

                            It's interesting that people who make money shooting videos don't want to see something graphical eg a graph and just want to know when the battery will die.

                            It's like wanting to get drunk but not taste the beer.

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                            • #15
                              I don't remotely get that analogy.

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