Understanding Lithium Polymer batteries

[Motopreserve]

Either that is not a lipo - or they are suggesting a low discharge as 2.5 volt - which for a lipo would kill it pretty quick. Regardless, depending on the size of your MR, 1000mah won't get you much flight time.

The battery also says 10C, so if your motors draw many amps, you may (or may not) go over the 10C discharge capacity.

Looks like you you should grab a couple new batteries.

 

[WacoJohn]

Either that is not a lipo - or they are suggesting a low discharge as 2.5 volt - which for a lipo would kill it pretty quick. Regardless, depending on the size of your MR, 1000mah won't get you much flight time.

The battery also says 10C, so if your motors draw many amps, you may (or may not) go over the 10C discharge capacity.

Looks like you you should grab a couple new batteries.

This is the battery provided by the copter's mfg. The whole pkg arrived today... new quad and their supplied battery (Parrot). You are absolutely right, . tried my first 3m hover on a 'full charge' and got about <5 minutes. I am a total noob at all this. It is a Ar.Drone 20 Elite. If you can recommend a battery .. I will buy two of them. I also need a 'smart' charger ... as a noob, not a clue what to get. Something well featured .. but not over the $$$ top. I think there is even something else good to have ... a 'balancer'? I would be privileged to follow your lead .. if you have any. thank you ... in advance.

 

[Motopreserve]

This is the battery provided by the copter's mfg. The whole pkg arrived today... new quad and their supplied battery (Parrot). You are absolutely right, . tried my first 3m hover on a 'full charge' and got about <5 minutes. I am a total noob at all this. It is a Ar.Drone 20 Elite. If you can recommend a battery .. I will buy two of them. I also need a 'smart' charger ... as a noob, not a clue what to get. Something well featured .. but not over the $$$ top. I think there is even something else good to have ... a 'balancer'? I would be privileged to follow your lead .. if you have any. thank you ... in advance.

Sorry, somehow I missed that you had the AR drone. I'm assuming you need to deal with particular batteries because of the size. Not sure. They seem to have a slightly larger capacity one as well.

You should see if you can research on a thread specific to that quad.

Good luck and fly safe.

 

[WacoJohn]

Hmmm. OK. Guess I will take that course for a charger, bearings, and 'balancer' too. Thank you very much for your advice.

 

[Bartman]

Hmmm. OK. Guess I will take that course for a charger, bearings, and 'balancer' too. Thank you very much for your advice.

John,

WHen you fly does the heli seem to have excess power that might be available to carry a heavier battery? you can't fly at full power but hoveruing at 65 to 70% should leave enough excess to maintain control throughout the flight.

If you think you have sufficient power to add weight via a larger battery then the next question is do you have enough room to add a bigger battery?

If it's yes to both then you should look to increase the capacity of the battery (total mah) without worrying as much about needing to increase the discharge C rating.

Hope that helps,
Bart

 

[WacoJohn]

John,

WHen you fly does the heli seem to have excess power that might be available to carry a heavier battery? you can't fly at full power but hoveruing at 65 to 70% should leave enough excess to maintain control throughout the flight.

If you think you have sufficient power to add weight via a larger battery then the next question is do you have enough room to add a bigger battery?

If it's yes to both then you should look to increase the capacity of the battery (total mah) without worrying as much about needing to increase the discharge C rating.

Hope that helps,
Bart

All I have done is charge OEM battery as instructed ... 90 minutes on their (minimal) charger. Hovered aircraft .. 3 meters ... up and down inside for maybe 5 minutes. Battery power down to 35%. Shut everything off. Do not want to proceed until I know more ...want to know if 35% is accurate, .. how to recharge from there, blah, blah.

Soooo, went to Amazon and bought 2x Parrot Ar Drone 2300mAh LiPo Replacement Battery Fits 1.0 & 2.0 Condition: New, 1 Set 8Pcs packaged Parrot AR Drone Quadcopter 2.0 & 1st Upgrade Drive Gear Bearings and 1 Dual Power B6ac 80w Super Multi Charger Balancer for Lithium (Li-po,), Ni-cd, Ni-mh, and Pb Battery. I hope to heck I did not waste any money.

http://www.amazon.com/dp/B00HED90RU/ref=pe_385040_30332200_TE_item
http://www.amazon.com/dp/B00FQ75QGA/ref=pe_385040_30332200_TE_item
http://www.amazon.com/dp/B00HVMGTV4/ref=pe_385040_30332200_TE_item

 

[FlyGirl]

I think you'll be fine with all that John but I did notice that one comment on Amazon regarding the charger said he had to order a separate 14-in-1 connector to mate the charger to the connector on the battery. Battery connectors are a PITA as you'll find out. There are far too many in use by manufacturers....

 

[WacoJohn]

I think you'll be fine with all that John but I did notice that one comment on Amazon regarding the charger said he had to order a separate 14-in-1 connector to mate the charger to the connector on the battery. Battery connectors are a PITA as you'll find out. There are far too many in use by manufacturers....

Wow ... THANK YOU for noticing that. I just went back to Amazon and ordered the Mega Charge 14-in-1 Charging Adapter. So glad you pointed that out.

 

[FlyGirl]

No prob and you're quite welcome

 

[jhardway]

good thread Bart, I have been doing a lot of reading in this, I recently added weight to my copter and lost some flying time but I have been trying to figure out if my 3.5 under load voltage can be dropped to a 3.3 which would bring me right back up to where I would like be. Right now if I fly to 3.5 and then charge the battery I end up only using 60% of the battery's capacity. So reading around I am finding mixed information on the what is an acceptable "voltage under load".

Either way thanks once again for the time it took for putting this together.

Best Jack

 

[Motopreserve]

3.36V would be adhering to the 80% rule, certainly safe (for the life of the battery at least) when it rises after landing/no load by a bit. I think the concern with going below 3.5-3.7 comes from experiences when the voltage may sag at the end of the safe/strong level, causing forced landings or worse.

 

[CdA D]

I understand the concern with the load below 3.5, but I have been flying my batteries at a 3.4 load for over 100 flights and have never had a issue. Now the question is what brand of batteries are you flying. If you're flying a less expensive battery then you should be concerned, but if you're flying a high quality battery then you should be good at 3.4. I fly only Thunder Power batteries. What is your aircraft worth? Good luck!

 

[mediaguru]

I've read every post in this thread. Amazing how different the battery "experts" can be on this subject. So tell me if I'm being too conservative. I'm running two 5000mAh 6S Pulses on my hexa. As soon as my Taranis telemetry tells me 3.7 volts, I land. When I've taken the load off the battery, they jump back up to over 3.8.

So I decided to let it go down to the 3.6 audible warning, which will kick in once a single cell drops below 3.7, such as 3.69. The battery jumps back up to about 3.75 volts with no load.

When I recharge them, as little as 2400mAh to 2900mAh is being put back.

Too conservative?

 

[cootertwo]

I know what you're saying, a lot of opinions, everybody has one. In my opinion, it rests on how much you like your batteries. Cheap. old batteries, who cares? Good expensive batteries, you take care of, don't overwork, over cook, or over use. The more you beat them up, the rougher they perform. Kinda like a good Woman !!!! Ha! But seriously, I have a few packs, that I mistakenly flew till flat, and they are "puffy" and don't have near the original capacity, and are not long for this world. I wouldn't try any lower than 3.6, just to be "sorta" safe. "In my Opinion.................":shame:

 

[FlyGirl]

I know what you're saying, a lot of opinions, everybody has one. In my opinion, it rests on how much you like your batteries. Cheap. old batteries, who cares? Good expensive batteries, you take care of, don't overwork, over cook, or over use. The more you beat them up, the rougher they perform. Kinda like a good Woman !!!! Ha! But seriously, I have a few packs, that I mistakenly flew till flat, and they are "puffy" and don't have near the original capacity, and are not long for this world. I wouldn't try any lower than 3.6, just to be "sorta" safe. "In my Opinion.................":shame:

+1 to that....!

 

[Roger Ramjet]

I agree with your concern. As previously stated here, if you are using half decent batteries with a respectable C rating (i.e. 25C+) you can approach you power management with the 80/20 % rule. That is to say that your batteries should require 4000 mAh on the recharge if you are using 80% of their advertized capacities. If you have a good charger, like Hyperion, you could perform a full cycle on the battery (discharge and recharge) to see the actual capacity of the battery.

Bringing the battery down to 3.3 v or so per cell on your charger with a small load (5A for example) and taking note of the actual capacity of the battery would be the first step. You have to make sure that your battery CAN give you the full capacity it is rated for. Most decent batteries often exceed this requirement. Once this is done, you can apply the 80/20 % rule and set whatever voltage that will require 4000 mAh to recharge.

I often select a loaded value (3.5 v for example) and I hover at low altitude for the last minute of the flight until my LVA flashes red (or until you see 10.5 volts on the OSD, if so equipped). After the battery cooled down, I recharge and check how much went in as you described. I will then tweak my voltage value until I get my 20% reminding in the battery.

Honestly, I often fly down to 14-16% and sometimes a little lower. I feel that as long as you do not abuse the battery with max power acceleration when the battery is getting low and vulnerable to high demands, you should not cause any damaged to your cells. Works for me...

So for shorts, IMHO, you are being a bit over conservative, however, absolutely no harm doing this!

Happy landings!

 

[mediaguru]

I did a very easy and low power flight tonight. Ran them down to 3.60. The difference between 3.7 and 3.6 equals about three minutes of flight time apparently. Once the load was off they went back up to 3.68. So naturally I'm a tad worried they didn't go back up to 3.7 off-load. They're charging now and I'll post back how many mAh they took back in. Very curious to find out. I get the feeling with these Pulses, which are supposed to be very good, I'm fine and could probably go more.

 

[mediaguru]

Well how interesting is this? I charged both Pulse 5000mAh 35C's on my paraboard. Total mAh put back in between the two batteries after running them down to 3.6 with load, 3.68 without load, was 7962mAh. That's 3981mAh per 5000mAh battery. Only 19mAh from being exactly 80%.

Comments?

 

[Motopreserve]

Well how interesting is this? I charged both Pulse 5000mAh 35C's on my paraboard. Total mAh put back in between the two batteries after running them down to 3.6 with load, 3.68 without load, was 7962mAh. That's 3981mAh per 5000mAh battery. Only 19mAh from being exactly 80%.

Comments?

you're right about where you should be. Safe and successful flights and healthy batteries. What is the concern? Is it flight time?

 

[mediaguru]

I was happy with 10 minutes, but thought I should be getting a few more minutes with my setup. Running the load value down to the low 3.6's versus 3.7's did buy me 3 minutes (30% more time), and it is nicely at the 80/20 rule.