The High Pro Glow

Welcome! The topics introduced in this blog will vary wildly. Here, you will find a lot of topics that might help some of those in need. I post off-beat information, hard to find history, & stuff that is otherwise seldom regurgitaited in our modern place. Sit back & find something interesting. Comment if you have a need or suggestion.

Thank you for crossing paths!

Christopher R. Smith (aka. Littlehorn)

I've got it on! Have you got it on?

Wednesday, January 18, 2017

Parrot Bebop 2 Battery Charging

The Parrot Bebop 2 battery pack provides the only means of power to maintain flight. How well and how long depends on a few easy to learn maintenance habits that will help Lithium-Polymer ('LiPo' or 'Li-Ion Polymer') packs perform as expected and live longer lifespans. Weakened LiPo packs can cause legitimate 'fly-aways' usually from bad cell voltage fluctuations leading to the unexpected system reactions to unusual battery behaviors..this also can trigger shutdown mid-flight. The Parrot battery packs are good quality but expensive and need attention like most other flight LiPo or they will die and take your Bebop too.

Ready for the meat of the subject now? It will be easy to understand and worth the effort. After you read this you will have a much better understanding of LiPo therapy. I will start with the Stock OEM Parrot Bebop 2 battery.

The Parrot Bebop 2 OEM battery pack is an encased 3-cell 2700mAh 3S 11.1volt LiPo. Parrot recommends "Charge at 3.5A Max" which is higher than the usual "1C charge rate" of typical R/C LiPo batteries. "1C" means that a battery can handle being charged at 1x the specified mAh written on a LiPo battery. Higher performance packs can handle higher than 1C charge rates..but more on that and connection details later.

LiPo Do-Nots...(one "Do"now..always watch LiPo charge)

-Do Not discharge below 10% remaining power as reported in FreeFlight Pro. Land well before this number or risk discharging below a safe voltage level for LiPo to remain healthy. Every dip below 3.2 volts per cell will add damage and shorten its life and harm expected performance. Failing cells will have voltage levels lower and weaker than the other cells. All of the cells should be about .2 volts within each other. A dying cell will not hold a charge as well as the others..or have the capacity. It could be target-charged to bring it up to match the other voltages and become balanced with the other cells...but it may be dying anyway. Discharging to zero equals LiPo death.
-Do Not store battery packs while discharged too low or with fully-charged voltage levels. Below 3.2 volts per cell is too low. Fully-Charged and it is like a grenade ready to blow. Flying a pack discharging it to about 45% to 60% as reported by FreeFlight Pro will pull the voltage level down to an approximate Storage Voltage Level or 3.75 - 3.85 volts per cell.
-Do Not let battery packs get too hot. At 140F damage occurs and where LiPo is at risk of rupture or 'venting'..like a volcano. If in your hot car or sitting on a charger too long in your home..the result can be disastrous. Normally, the battery only should be a little warm after a flight. LiPo likes to be about 95F at lift off summer and winter. Though, let the battery cool down between charge cycles and flight.

Note: FreeFlight Pro reports remaining battery charge measurements taken during flight. Voltages fluctuations can cause reporting errors. A failing battery may even dump or fail to supply voltage demands to the point the system shuts down..and the Bebop falls. Cold weather has the same affect on all LiPo chemistry cells.

Now, the "Do's" will be explained in the handling and charging processes described below. New LiPo packs need a few cycles after birth/storage to perform as expected and become trusted for expected flight performance. So, don't trust them for a few flights..keep the Bebop low and slow until you get a good feel for a battery's behavior and performance before you get too far down the road.

Charging the Bebop batteries with the included stock charger is not a great solution to continue for long. The batteries can be discharged below the level that triggers the stock charger to start charging. Some tricking could force the stock charger to charge..but it isnt recommended as the battery may be damaged and forcing it to charge may become a bigger problem with smoke a fire. Some Bebop 2 boxes have been on the shelf for a year or more at this point in time. Batteries from new sealed boxes can self-discharged to unhealthy level and may not be capable of supporting safe flight. The stock charger do not provide any information about the pack or its status. Without a way to monitor your batteries it is impossible to know enough to keep the Bebop flying as expected for as long as expected. The stock charger can balance the packs well enough for 6 months of fun. But, these packs can usually live a much longer and more productive lives.

To Charge a Parrot Bebop 2 Battery pack..first, stop using the stock charger. Then, find a better balance charger with a display that can do more and show you what is happening with the LiPo cells. I use the one pictured here. It is very capable and more modern and being actively supported..more than 4-button chargers these days. 4-button chargers are really good and some offer some really great functions. Most of the veteran users will use them. New chargers are being released often. The iSDT chargers are very easy to use, updatable, and have performed better than my 4-button chargers.

Here is my iSDT SC-620 charger connected to a Bebop 2 battery. The custom adapter cable shown in the pic is needed to complete the setup. That adapter is hand-made and different versions can be purchased from different sources. If you wish, you can contact me..I will be making several different versions for different applications for North American users. If you have basic solder skills or want to learn how to make your own cable..watch Clifford Rascanni's video: https://youtu.be/orESacSy2ro



The short main power portion has an XT-60 connector (yellow) soldered on the end leading to the charger's main output. The XT-60 is a very common connector used with many LiPo batteries, chargers, and other RC systems. Usually, this would connect to an adapter supplied with the charger to complete the connections.

NOTE:  Both the 4-wire balance lead and the 2-wire main power lead need to be connected to the charger to be able to balance charge the internal cells properly.

Due to the flexibility of the iSDT chargers, it is possible to charge a LiPo battery with a larger LiPo battery, or from a larger deep-cycle 12volt battery, or from an old PC's power supply, or with an old 12volt 5Amp laptop power supply from a wall plug. Since this is a fact..a power supply is also needed to power the iSDT chargers. There is an  included 12volt adapter with alligator clips and the XT-60 that matches the iSDT charger's power input port. Other options will need the XT-60 to match the charger. If soldering is not your preferred method of DIY..you need to find the appropriate adapters to complete the connections.


An optional charge setup requiring less work upfront are 4-button chargers. Below is a Tenergy TB6B 4-button charger connected to the Bebop 2 battery. Many 4-button chargers include a 'squid' connector lead with an assortment of common connectors to match most systems in use today. Some 4-button chargers will need a power supply. The Genuine SkyRC Imax B6ACv2 has an internal power supply making it a little easier on beginners. Most 4-button chargers use 4mm banana plugs to output the main charge current to the battery lead..I have one with the yellow XT-60 connectors as seen in the picture. Other good brands of 4-button chargers are available. Just be sure to buy "Genuine". Adjustments can be made to most of these units to better calibrate its measurements. But, usually most of them are close though the readings may not be in sync with every other voltage meter that isn't calibrated either.

Setting a charger to charge a Bebop 2 battery.

Generally..make sure that you are charging to the battery's specs as labelled on the battery and that the charger is always set to "Balance Charge"..Not "Fast Charge" or even just "Charge". Both the 4-wire balance connector and the 2-wire main lead connector have to be connected for the charger to balance charge the internal cells properly. When balance charging, the input charge is individually added to each cell and they are increased equally until fully-charged or when the set cut-off voltage is reached. Most chargers will automatically set some aspects like battery type, cell number, max charge voltage level cut-off, discharge voltage level cut-off, a set storage level voltage, and possibly a charge rate amperage value. Nothing to sweat about.

Balance charge Bebop 2 batteries at a 3.5Amp charge rate or below. This setting is important..and selectable before starting a charge process. Some tests suggest that lower/slower charge rates help achieve a longer LiPo lifespan. I wouldn't recommend trickle-charging the batteries throughout the charge cycle because it would take a long time to charge and balance high-capacity 3S packs and there is no real benefit by charging slower than half the C rating. A 2700mAh pack (such as the B2 stock battery) has a C rating that suggests it can be charged at 2.7Amps. However, as mentioned before, Parrot recommends "Charging at 3.5A Max" which is higher than a usual 1C charge rate of LiPo batteries. I have charged one of mine at 3.5A for over a year with no signs of damage. 2.7A is the safest rate for B2 stock batteries and should provide the best overall longevity as well.

Whatever charger you do employ..watch the charger or be near it while it is powered on and especially while charging anything.

Keep it Safe. Keep it Healthy. Enjoy the Skies!

5 Comments:

At 2:15 PM, Blogger Warren said...

Hi,

Thanks a lot for this post, it's very helpful. I'm charging my Bebop 2 battery with a UAC-50. I flew the drone till the battery reached 2% and have balance charged it back up as one cell was quite a bit below the other two. It's been going for 75 mins and the batteries are at 12.60v (which the charge end voltage is set to) and is now charging at 0.7a, the individual cells are reporting 4.19-4.20v together. Is this right? The mAh it's put into the batteries is around 2350 so far. How does it know when to stop? The capacity cut-off setting on the charger is set at 5000mAh, should I have changed this to match the batteries capacity? It's an aftermarket 3100mAh battery I'm currently charging. Only got the cable and charger today and it's my first attempt with these so any advice on this is greatly appreciated!

Thanks a lot!

 
At 7:10 PM, Blogger ewoid said...

Christopher:
Thank you for this very informative blog. Being a Bebop 2 flier can be frustrating, and it's great to have someone like you around to help.

Do you still make the adapter cable for charging the Bbp2 batteries with a balanced charger? I just discovered how necessary it is to do this, and I am lucky enough to have a buddy who had a Imax B6AC charger he would sell me.

Please let me know if you can make me one or two of the cables and connectors as soon as you can. I'm in SW Washington state, and our summers are wicked short and often rainy (though since the beginning of June, it's been great. But up here, you never know.).

Please contact me at ewoid64@gmail.com and let me know.

Thank you for any help you can offer.

Tim Tully

 
At 2:08 PM, Blogger Christopher R. Smith (Littlehorn) said...

Hi Warren..Discharging to 2% can be below a healthy bottom level of 3.2 volts per cell. Try not to discharge any cell below 3.2volts. Beware of the flight system's battery level numbers being a different measurement and scale. Get very familiar with bolt age checks before&after charges&flights.

The catch with sevetal devices is if any are actual accurate to their displayed numbers. Calibration is always suspect until it can be verified. So, "4.2v" max may actually be higher and stressing the batteries. Setting the charger's max charge cutoff is Ok. Set it to 2700mAh if that is the largest pack you charge. But, this number is a total capacity...you only replace a portion and that is different each time. So, feeling-out how your batteries respond when being topped-off or verifying the accuracy of the charger will help to determine if you need to lower the voltage to 4.18v or 4.19v..or lower to keep this level from being exceeded and allow a safety zone before overcharge. Flighttimes are not greatly altered by lowering the top-off voltage.

 
At 2:10 PM, Blogger Christopher R. Smith (Littlehorn) said...

I will contact you. I can make cables or hack the Bebop 2 stock charge cable.

 
At 9:02 AM, Blogger John Horton said...

Best information I have found yet! Tired of ruining these batteries and wondering if I will ever see my Bebop again. I would be interested in purchasing an adapter cable, if the offer still stands. I am in South Carolina and any help is very appreciated. my email is jhorton@georgetownlandingmarina.com. Thank you.

 

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