Archive for the ‘Li-Po/Ion/Fe Batteries’ Category

2s-life-700-mah-zippy-5c-battery

The 2S 6.6V 700 mAh Zippy Flightmax LiFe batteries are intended for use as a receiver battery packs in remote control models using nitro engines, but they can also be used as a main battery in other remote control cars and other RC models. The Zippy brand is used by one of the largest Chinese online stores for radio controlled models and is considered to offer good quality at a good price, but as with other cheaper Chinese lithium-based rechargeable batteries we are expecting to get results a bit lower than advertised, but let us see if we might be pleasantly surprised this time…

Official Battery Specifications:

– Capacity: 700mAh
– Voltage: 2S1P / 2 Cell / 6.6V
– Discharge: 5C Constant / 10C Burst
– Weight: 41g (including wire, plug & case)
– Dimensions: 53mm x 30mm x 15mm
– Balance Plug: JST-XH
– Discharge Plug: Standa JR Servo plug


2s-life-700-mah-zippy-5c-battery-capacity

We have started the tests with a 1C discharge rate (0.7A) for the 2S 6.6V 700 mAh Zippy Flightmax LiFe battery and we’ve managed to get 653 mAh as a maximum capacity, a value that is a bit shorter than the official rating of the battery of 700 mAh. So the battery should’ve been labeled 650 mAh instead of 700 mAh as apparently it cannot provide 700 mAh at 1C discharge rate, but the interesting thing is that this battery can provide the same capacity with a discharge rate of up to 3C and going to the maximum rating of 5C as a constant discharge rate we are seeing a bit of a decrease in the useable capacity where we got 599 mAh. So the discharge rating is Ok, the capacity however is labeled with 50 mAh more than it should’ve been, in the end these batteries are handling pretty well, so if a 650 mAh LiFePo4 battery is what you need at a good price, then you might consider getting these Zippy Flightmax batteries.

The performance of the 2S 6.6V 700 mAh Zippy Flightmax LiFe Battery in our tests:

– 653 mAh at 0.7A load (1.0C)
– 653 mAh at 1.4A load (2.0C)
– 653 mAh at 2.1A load (3.0C)
– 599 mAh at 3.5A load (5.0C)

What you should have in mind here as well as with other small batteries that use thin cables passing higher current such as 10A (the burst load rating of this battery) or even higher as a constant load is not a good idea as they will get hot and may melt and short the battery, and that is definitely something you don’t want!

2s-6-6v-2000-mah-robitronic-life-battery

2S 6.6V 2000 mAh Robitronic LiFe batteries are intended for use as a receiver battery packs in remote control models such as nitro cars – to power the servos for throttle and steering as these cars use fuel not electricity for their engines. The good thing about LiFe batteries is the fact that they have much steadier discharge curve than traditional LiPo batteries, so they can provide a more constant voltage under load in almost their full capacity. Since however the manufacturer or the brand Robitronic that these batteris go under does not give a lot of details we’ll need to check how good these batteries actually are. The 2S 6.6V 2000 mAh Robitronic LiFe battery uses two cells to provide 6.6V and each cells consists of two smaller capacity cells that should be 1000 mAh each meaning that the battery is 2S and 2P (two cells in series and 2 in parallel).

Official Battery Specifications:

– Capacity: 2000mAh
– Voltage: 6.6V
– Dimensions: 56 x 32 x 32 mm


2s-6-6v-2000-mah-robitronic-life-battery-capacity

Starting the tests with a 0.5C discharge rate (1.0A) for the 2S 6.6V 2000 mAh Robitronic LiFe battery we’ve managed to get 1.77 Ah as a maximum capacity, a value that is a bit shorter than the official rating of the battery. So it seems that instead of 2000 mAh this LiFe battery is more like 1800 mAh and the good thing is that it can handle very well higher loads such as 10A constant discharge while still providing almost the full capacity it offers. Not that you will need constant loads of up to 10A for the servos in an RC model, but you can be sure the battery can handle even higher peaks without problems.

The performance of the 2S 6.6V 2000 mAh Robitronic LiFe Battery in our tests:

– 1.77 Ah at 1.0A load (0.5C)
– 1.76 Ah at 2.0A load (1.0C)
– 1.75 Ah at 5.0A load (2.5C)
– 1.73 Ah at 10A load (5.0C)

What you should have in mind though is that as with other small batteries that use thin cables passing higher current such as 10A or even higher as a constant load is not a good idea as they will get hot and may melt and short the battery, and that is something you don’t want for sure.

2s-7-4v-350-mah-gens-ace-30c-lipo-battery

The 2S 7.4V 350 mAh Gens Ace 30C LiPo batteries are intended for use mostly in aircraft RC models such as helicopters and planes. These compact LiPo batteries have a pretty high discharge and charge ratings that we need to confirm in our tests. What is important to note is that the maximum discharge rates mentioned in the specifications are for quite high Amps and the small cables and connectors of the battery may not be able to handle them well.

Official Battery Specifications:

– Capacity: 350mAh
– Voltage: 7.4V
– Max Continuous Discharge: 30C (10.5A)
– Max Burst Discharge: 60C (21A)
– Weight: 25g
– Dimensions: 54,2×30,2×7,8 mm
– Balance Plug: JST-PHR
– Discharge Plug: n/a
– Charge Rate: 1-3C Recommended, 5C Max


2s-7-4v-350-mah-gens-ace-30c-lipo-battery-capacity

Starting the tests with a 1C discharge rate (0.35A) for the 2S 7.4V 350 mAh Gens Ace 30C LiPo battery we’ve managed to get 381 mAh as a maximum capacity, a value that is about 9% higher than the official rating of the battery, so definitely a good thing here. Furthermore up to 25C constant current discharge rate the battery still manages to provide 363 mAh, still more than the rated capacity, though at that rate we’ve measured the battery ending up discharged with a temperature of 68 degrees Celsius or a bit high than the 60 degrees safe zone. The more serious problem however became apparent with the 30C constant current discharge rate test where 10.5 Amps need to pass through the small cables of the battery and this makes them very hot – up to 100 degrees and that is dangerous as they or the connector can melt and short the battery!

The performance of the 2S 7.4V 350 mAh Gens Ace 30C LiPo Battery in our tests:

– 381 mAh at 0.35A load (1C)
– 378 mAh at 1.75A load (5C)
– 376 mAh at 3.50A load (10C)
– 375 mAh at 5.25A load (15C)
– 370 mAh at 7.00A load (20C)
– 363 mAh at 8.75A load (25C)
– 287 mAh at 10.5A load (30C)

While the 2S 7.4V 350 mAh Gens Ace 30C LiPo batteries are capable of handling a constant discharge rate of up to 30C as their specifications say the battery cables used are not designed to properly handle the 30C constant discharge rate!


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