HEIOKEY 6pcs Upgrade 3.7V 520mAh 25C LiPO Battery with X6 Battery Charger for Hubsan X4 H107,H107C,H107L RC Quadcopter,Syma X11 X11C,Holy Stone HS170 HS170C F180C Compatible with Walkera Super CP

The charger works very well, although it does slightly overcharge each battery to about 4.28 volts. The voltage returns to at or just below 4.2 volts after removal from the charger. It charged all 6 batteries from storage charge voltage (3.8 volts) to full charge in < 30minutes using a 2.5 amp USB power cube. Each battery has an individual charge controller, as each LED winked off individually. The unit is well built and great for ultra-portable field use. I have an Imax B6 Mini charger with parallel charging cable I will normally use for these batteries, but having this little charger is a nice plus for backup. I bought the batteries for use in a Syma X11C quadcopter. The batteries are over twice the capacity of the original 250 maH cell. However, they still slide easily into the battery compartment and are almost fully enclosed. Very nice. The extra weight of the battery is well-distributed and affects the trim and balance if the X11C very little. However the flight characteristics are different because of the added mass and inertia. More opposite control is needed to counter movement. Changing to high rates on the remote seems to help. I found I adapted to the added weight after only a few flights. Battery life in the X11C is much longer, although I did not time my flights. Power is greater, but needed to manage the extra weight of the cell. I noticed that on a few cells, the X11C cut off the voltage at a VERY low level, around 2.8 volts. This is far below the recommended 3.3 volts and could cause damage to the cell. However, after a few charge cycles, this no longer happened and the X11C cut off the flight at around 3.3 volts, the normal cutoff voltage. The physical quality of the batteries are excellent. The leads are heavy gauge with quality connectors. Each cell is well wrapped and none of the cells had any puffiness. The physical dimensions are also very consistent. I have parallel charged up to 5 cells at once on my Imax B6 Mini charger with great success. The cell voltage characteristics and internal resistances that I measured are very consistent. A great value. I am very pleased with the purchase. UPDATE: I discovered something interesting. When one of the cells discharged to a very low voltage, I found that the battery appeared to be dead. It would not even register on my voltmeter. However, it accepted a charge just fine. It turns out that these batteries do have a circuit within that protects the battery against over-discharge, short circuits, and excessive charge current. This is a very good safety feature, as dropping the cell below 3 volts can cause permanent damage and a dead short can cause melted plastic or a fire. I have charged the batteries at up to 3C (1.5 amps), but much higher and the current seems to self-limit in the battery, even though the charger is set for a higher current. I would say this is a very good feature. The circuit seems to add very little internal resistance to the cell, so performance is hardly affected.

Bought for use in Syma X11C. First off, these things last a ton longer than the stock battery - I haven't timed any flights but I'm guessing around 10 minutes - and that's flying outside in fast mode. The 6 port charger is great - still a 30-40 minute charge time, but beats the crap out of the single port charger that came with the quad. I did take the time to label the ports and their corresponding LED - helps take the guesswork out of which battery is done charging. The batteries fit into the X11 just fine, but stick out the back a bit more than stock (they are longer, so that's expected). The fit is not as snug as the stock battery, so I've found that after a hard crash or other impacts the battery will slide out a bit, which drastically alters flight - you have to re-insert or you won't be able to fly. Pros: Great upgrade battery for Syma X11 - much longer flight time Can charge 6 batteries at once Black tape at wire/plug connection to prevent wires from pulling out Cons: not a perfect fit - battery will start to slide out after impacts

one battery seemed to go bad early on with fairly strict attention to handling, the charger can be fiddly. Overall being able to charge all batteries at once and have multiple batteries charged is essential to those trying to advance their skills. These batteries and a Hubsan X4 H107L or C model or three Make an unbeatable intermediate pilot training package bang for buck. Also runs other quads just fine.

I bought this charger and batteries set for my Hubsan X4 H107P. Perfect fit, and they seem to be a bit more powerful than the stock batteries. Charging time is about 45 minutes. The only issue I had was with a couple of the connectors not releasing easily but a needle nose pliers gives a better grip and I had no problem. Great price, great battery set. I'll update this review if my opinions change after extended use.

Update!!! I raised my rating to 5 stars based on the amazing customer service from HEIOKEY. I just received my replacement charger and it seems to be working perfect. I just want to say a special thank you to Fiona who was amazing with her attention to customer service. I will definitely be ordering more from HEIOKEY as needed. I can't say enough about their customer service thank you again HEIOKEY and thank you again Fiona. I will do a product review of the new charger once I get a couple charges through it and let you know how it works. I received the battery charger and 6 batteries from HEIOKEY in time and in good condition. After about 3 charging cycles, the charging ports began to fail. Only 2 ports are currently working. I'm sure it is just a factory defect and a replacement charger is on the way. Fiona my customer service rep, has been amazing with trying to help resolve the issue. She said she will be sending me a replacement charger once this review is published. I will update this review once the new charger arrives. I will do a test of the new charger and report back to Amazon. Thank you again, Fiona from HEIOKEY, for all your help with this matter. Brian