Hello, I am a newbie to this forum and am no expert on drones. A couple of years ago I saw the Hubsan H501s and it was in my price range, $200-$400. Especially after having numerous "Toy" drones go where ever they want. I have not had any issues with it for the past years until today. We live in NW PA so its a rare occasion to get to fly in April. All went well, and I charged my batteries back up. They are 7.4V 2700 Mah, I use a Tenergy charger. I may have messed up as I did not drop the voltage in the batteries to the storage voltage. This is going to be where I show my ignorance. I tend to keep the Lipo's at full charge because I never know when weather will allow me to fly. I have heard that you should drop the voltage to Storage voltage if you are not going to fly for a couple of days. Can someone in the forum tell me the who, what,when etc of taking care of Lipo's. Charging, etc, all the pertinent stuff that impacts Lipo's. In this case, the Lipo 2700 showed on the meter that it was at 100% (I had 3 more the same, and they were charged up months ago.)
To continue my saga, Both the transmitter and drone had full 100% batteries that were charged at least 3 months ago. All seemed fine, Itook off, flew around a bit with the camera taking video. At about 6 minutes I notices the drone battery was way low, 6.6V, So I started a rapid descent, then turned on RTH to let it bring it down from about 135m, it was straight above me. Then it went wacky, the drone was at a low Voltage,6.6V, the controller was fine, but the drone started in a spin as if it was completely out of control, which it was. I have never seen one go into a spin, but it did. It dropped out of the sky, off I went for the search, I took pictures of the GPS coordinates on the transmitter because I thought it was in a hay field. Here is what I don't understand, it crashed into the top of a tall oak tree, it was still taking video at 11 minutes and the drone VOLTAGE was at 7.3V . I plead ignorance in so far as proper care and charging of Lipos. I don't know if this is the cause of dropping out of the sky in a spin at 6.6V and crashing into the tree and having 7.3V. Was it caused by a battery? I have 5 2700 7.4 Lipos that I have not put into a storage voltage, did I screw these not cheap batteries up?. They always will charge up to a 100% and I don't drop to storage V. Is this Bad?
So bottom line is, any ideas why I would go into a spin and crash?? Never have happened before, and secondly I would appreciate any info on what to do, and not do with Lipo's, Are mine any good after being charged up full for months, or does that ruin them, screw them up somehow. I still don't know the fate of my drone as its still up 80' in a oak tree. I like my Hubsan, but am asking you guys, the experts if there are others that are good drones between $200 - $400? I want a decent camera, HD 1080 with decent amount ofMegs/resolution. Gimball camera is not a necessity, GPS, Headless, RTH, Follow me are wants, as well as SD card Video recording, FPV with a monitor preferably on the transmitter rather than using a smart phone. If my Hubsan is broke, I'll be looking for a new one, but not being an expert, there are so many drones out there , its hard to choose what the best is for the money. I like the size of the Hubsan, and brushless motors and at least 7.4v batteries are probably a good idea also.. I want to thank you in advance for any ideas, thought, information, etc regarding what may have happened that caused the low V and crash the V come back up, info on Lipo's and any other stuff that I would find useful. THANK YOU!!
Proper Care & Treatment: Storage
In the old days, we used to run our cars or airplanes until the batteries died, then just set the batteries on the shelf at home, waiting for the next time we could use them. We just stored them dead. But you should not do that with LiPo batteries. Nor should LiPo batteries be stored at full charge, either. For the longest life of the batteries, LiPos should be stored at room temperature at 3.8V per cell. Most modern computerized chargers have a LiPo Storage function that will either charge the batteries up to that voltage, or discharge them down to that voltage, whichever is necessary.
Proper LiPo Storage Voltage = 3.8V per cell
I recommend to our customers that they put their LiPo batteries in storage mode after every run. This isn't necessary per se, but it does build up good habits. If you do it every time, you don't have to worry about whether or not you remembered to put it in storage. I have had many customers come to me with batteries that died because they charged it up, intending to use it, but life got in the way and they never remembered to put it back to storage voltage. Lithium-Polymer batteries can be damaged by sitting fully charged for as little as a week. This doesn't mean they will get damaged every time you leave them for over a week. It just means they can, and I've seen it happen. So don't forget to put your LiPos at storage voltage when you're done using them.
They should also be stored in a fireproof container of some sort. As I mentioned above, most people tend toward leaving their LiPos in a LiPo bag, as they are portable and protect your workshop from catching fire should the LiPo combust. I have also seen people use empty ammo boxes, fireproof safes, and ceramic flower pots. Whatever you have (or can buy) that will prevent any fire from spreading will be worth it in the unlikely event that anything untoward should happen.
I feel the need to reiterate: the most common problem people have with LiPo batteries is a direct result of improper storage. When a LiPo battery sits for a long period of time (and not at proper storage voltage), it tends to discharge itself. If it drops below 3.0V per cell, the vast majority of LiPo chargers will not charge it. Sometimes, batteries with this problem can be rehabilitated, but just as often, they are a lost cause. So again: if you take a 'laissez-faire' approach to the storage of your LiPo batteries, it's entirely likely that you will be purchasing new batteries sooner than you think
Hi just to add ,I have loads of batteries so know the problem ,but what I do is keep them at storage charge you can do a fast charge , this is not wacking volts in fast what it does is charge normally but does not do the final balance which takes the time when charging but it will be enough to get a flight in , then next time do a balance charge