I have been reading a lot of the threads on batteries lately and it got me thinking about when I charge mine compared to when I fly. I fly my Cinestar 8 basically every week for aerial photo shoots and have routinely come home, unpacked everything and re-charged all the batteries that were used for the day. I mostly fly QC 8000s and use a variety of the QC 1200s for downlinks, receivers, monitors, etc. I carry some QC 6200s as backups in case I need them. While flying, I normally discharge the battery about half way or a little more and then start my landing. Its pretty common for me to use about 5000 - 6000 mAh of the 8000 in a normal flight. My question / concern is about the time they sit charged before the next flight. Is a few days OK, is a week or more OK? I am wondering if I should be coming home and doing a storage charge on the battery (or just leave them in their discharged condition from after the flight) and wait until the night before I know I am flying to do the full charging of all batteries. If so, would that suggest that a person should discharge the unused batteries for the day if they are not going to be used again for a week or so? If I end up doing that un-necessarily, am I just creating wasted charge and discharge cycles on the battery and shortening the life that way? This is especially relevant for the back up 6200s that I carry and rarely use - and if I get my shots on less QC 8000s that I had charged up for the day. Finally, after seeing the fancy case that Tabb was displaying the new Flight Pack 9000s in I am also wondering if keeping them in an insulated case / pelican, etc is another best practice. I currently keep them in a camera accessory pack so they don't ever sit in direct sun or anything, but nothing like the case I saw. Since a battery failure in flight equals a crash I am looking for the best way to care for them and for the "ounce of prevention" techniques that others are using to keep your batteries fresh and healthy. Thanks! Michael
The conventional wisdom (and I don't have hard data to back this up -- it's just anecdotal from what I've read and heard) is to keep them fully charged for no more than 24 hours. So, if you charge them up the evening before flying and you live in Oregon (which means the weather will be crap tomorrow), then wait to see if it's going to clear -- if not, use the charger to discharge the batteries back down to storage charge. I'm sure this is not a step function, so you won't trash the batteries if you stretch it to keeping them charged for 48 hours, but I don't think it does them any good. As Brad can attest (he was over at my place today), my strategy is to charge them batteries on the day of a shoot -- which is why I have four Hyperions so I can charge eight at a time. I think I may need to buy a couple of test batteries and keep one fully charged and one at storage voltage, and then, once a week, charge them both up fully and discharge them through my battery tester once a week, and see if I can see any measurable difference emerging between the two batteries based upon how they are stored. Andy.
Thanks Andy. I will definitely be adjusting my battery procedures and plan to charge the night before - and since I carry a 12V marine battery and 2 of the Hyperion chargers out in the field most of the time, I may not charge a bunch of 6200s as backups either. Probably best to just charge what you think you are going to use for the day and have the ability to charge more if it looks like it is going to be necessary. What do you keep them in when out in the field? I've seen cases with nice foam inserts, heard people use coolers to insulate from the really hot or colds temps. I deal with the heat, so I am looking to keep them from getting un-necessarily hot while left in the car or somewhere without shade or other protection from the sun while flying. Finally, I did a little searching on your idea about proper storage voltage vs storing at a full charge and found this to give us an idea of the damage it causes storing a battery at a full charge (hopefully this saves you the hassle of doing the test!)
Hi Michael: I use a flexible insulated storage bag or a insulated cooler box (which acts as a "warmer" in the winter). I put discharged batteries in the "cooler" to provide some heat. Brad (one of the other moderators) mentioned that for really cold shoots, he puts "Hot Hands" hand warmers into the "cooler" to provide additional warmth. Thanks for the table above. Yeah, bad news to store LiPo's fully charged, I'm afraid. Andy.
Thanks again. So for the hot weather conditions do you think a pelican case with pick and pluck foam would keep enough heat out - even if left is a van while its 90 degrees outside?
I doubt it. I'd really be tempted to get an insulated cooler. Inside a van with external ambient at 90F is likely to to be way too hot inside. You could use a six pack as a coolant source. Or two. Andy.
Great discussion. Good find on the storage chart. Compelling advice to stay at store charge until w/in 24 hours of flight.
Order some steaks from Omaha Steaks. They ship them in an outstanding styrofoam cooler. Eat the steaks, use the cooler for keeping lipos warm or cold.
What's the consensus about keeping batteries fully charged for a few days or a week? I feel like there's a balance between charging up batteries, then discharging them to storage voltage, then charging them back up (within a week, for example), versus just leaving them charged. For example, I charge up several pairs of batteries for a shoot, and let's say one pair of batteries doesn't get used. I have another shoot in less than 1 week. Do I discharge the unused batteries or leave them charged? Given that most of these LiPo batteries seem to have a finite number of charge/discharge cycles in them, I wonder about "wasting" a cycle if just leaving it "as is" won't hurt it (for a few days). Your thoughts?
I suspect that the damage done by holding the battery at full charge outweighs consuming the number of charge cycles, but that's me speculating. I can see that "Battery Tester" could be a full time occupation -- it really would be nice to know the answers to these kinds of questions. Andy.
I was thinking the other day that we may end up with "smart" batteries like the ones in laptops that track some of their usage and performance data inside the battery itself. There's a bit of smarts in each Macbook Pro battery. My Macbook Pro's battery tells me lots about itself when I ask: Battery Information: Model Information: Serial Number:9G223008HDN5A ManufacturerP Device Name:bq20z951 Pack Lot Code:0 PCB Lot Code:0 Firmware Version:301 Hardware Revision:1 Cell Revision:119 Charge Information: Charge Remaining (mAh):8370 Fully Charged:No Charging:No Full Charge Capacity (mAh):12427 Health Information: Cycle Count:178 Condition:Normal Battery Installed:Yes Amperage (mA):-2567 Voltage (mV):7685
And transmitters that automatically shut off charging when they're done (and a little LED that tells you when it's charging and when it's done). Jeez, c'mon Graupner, Futaba, Spektrum.... Andy
Steve, This was the exact type of scenario that I was thinking about when making the original post. I too tend to have everything all charged up for a shoot and then seem to end up with some unused batteries when I return home - as well as I had been putting the used ones on the charger when I got home to get ready for the next shoot - which could be days or sometimes longer. Of course there are always the weather cancellations (rain, wind, etc) which leaves me hoping to get back out in a few days...days which can quickly turn into a couple weeks (and I still have all the batteries charged and waiting). It definitely seems like the right thing to do is put them on the charger in storage mode and wait until right before the next shoot to recharge everything. I found other people discussing this issue and commenting that they literally try not to leave a pack fully charged more than a couple hours. I hope your prediction of a smart battery is on the drawing board for someone. We really depend on these thing to perform without any failures. All the efforts to charge, discharge, etc would sure be nicely complimented with some good info on the true health, age and remaining / expected cycles left on the battery. I was hoping to do something like this for storage and transport (in a hot climate) but need to get a wireless oven thermometer or something similar to see what the temp inside the case would get to (with and without the foam that would probably act as insulation) if left in a van while it was 90 degrees outside. I certainly will not be needing another $2000 pile of poorly cared for lipos! I am done learning this lesson........I guess this really creates a good excuse to "need" a nice case of 10 of these new free fly flight packs.
The fastest way to take the batts down to Storage is to fly them -- so I find sometimes I'll just come back from a shoot, go to the local park and, to use the Britspeak phrase, just naff about the sky for a few minutes, relaxing (to the degree one can relax with $10K dangling from plastic props, the shafts of which are held in place by tiny spring clips....) Of course, if I stagger back home late in the day, then the Hyperion's get used to drain charge. Electrons all over the carpet, there are.... Andy.
Wouldn't it also be cool if we could hook up our charged-up LiPo batteries to our home electrical system and feed that power back into the house like you do with solar panels? Or maybe just run the toaster or something? Or maybe I can jack 'em into my Ford Escape Hybrid for the drive home. It troubles me to waste all that electricity. Oh, the possibilities...
Anyone using the Graupner Lipo battery for the MX20? I just got one but have not charged it yet. If you are using one, do you storage charge your transmitter battery like your flight packs? I guess whats one more battery to charge and discharge each time - I can appreciate Andy having 4 chargers and being able to maintain 8 batteries at a time.
I don't storage charge the Graupner LiPo. I've got a total of 3 and when they run down charge them up. You should get 5-6 hours in an MX-20 and I get about 4 hrs in an MC-32. That's down to about 40% on both TX's. Yes you can charge them on your Hyperion just as a regular LiPo. You will need some type of adapter cable to connect to the servo plug on the battery. You might also see a warning about no balancer, at least I get it on the Hyperion. Just continue on through that message since it can't be balanced, no balance plug.