The 2S 7.4V 500 mAh KingMax 25C LiPo batteries are compact packs used for remote controlled models that re supposed to offer decent performance for their small size. The batteries are rated for 25C constant discharge rate and higher burst ones, but are these batteries really capable to deliver such performance?

Official Battery Specifications:

– Capacity: 500mAh
– Voltage: 2S / 2 Cell / 7.4V
– Continuous discharge rate: 25C
– Charge time: recommended (1A/2C)
– Net weight: 30g
– Size: 53 x 30 x 10mm


We’ve started testing with a 1C discharge rate (0.5A) and the 2S 7.4V 500 mAh KingMax 25C LiPo battery was able to give out just 438 mAh capacity which was a bit disappointing considering the battery is rated at 500 mAh, this is a little over 12% lower capacity that advertised. Moving to higher discharge rates such as 5C and 10C (5 and 10 times the capacity) the battery handled quite well. At 15C constant discharge rate in the end the temperature of the battery was a bit hot at 55 degrees Celsius (still within acceptable levels) and the capacity provided was already less than half of what the battery could provide at 1C discharge. Moving to 20C discharge rate the battery reached the cutoff voltage very quickly, so the 2S 7.4V 500 mAh KingMax 25C LiPo batteries are definitely not able to handle 25C constant current load when they have trouble even at 20C.

The performance of the 2S 7.4V 500 mAh KingMax 25C LiPo Battery in our tests:

– 438 mAh at 0.5A load (1C)
– 429 mAh at 2.5A load (5C)
– 412 mAh at 5.0A load (10C)
– 207 mAh at 7.5A load (15C)
– 38 mAh at 10A load (20C)
– 22 mAh at 12.5A load (25C)

In the end 2S 7.4V 500 mAh KingMax 25C LiPo batteries turned out to be a bit of a disappointment with more than 10% lower actual capacity than advertised and not even close to the discharge rates they are supposed to provide. These batteries should have been rated at not more than 440 mAh capacity and discharge rate of 10C-15C and not 25C as they claim to be.


The 2S 7.4V 350 mAh Zippy 20C LiPo batteries are small Lithium Polymer batteries mostly used in remote controlled planes and are available at really bargain price from Hobby King. They are 2S1P batteries with a capacity of 350 mAh and should be able to handle 20C discharge rates (20 times their capacity) according to the official specifications. These specifications seem quite reasonable, however we are still going to check if they are true in reality or not.

Official Battery Specifications:

– Capacity: 350mAh
– Voltage: 2S / 2 Cell / 7.4v
– Discharge: 20C Constant
– Weight: 21g (including balance & discharge plug)
– Dimensions: 40x20x15mm
– Balance & Discharge Plug: JST-XH & Mini JST plug


We’ve started the capacity tests of the 2S 7.4V 350 mAh Zippy 20C LiPo batteries with a discharge rate of 1C which was handled without any issues, though the maximum capacity we got was 337 mAh or a bit short of the 350 mAh that they should provide. Then moving to higher discharge rates of 5C with no problems, next was 10C discharge rate that the battery still managed to handle without issues even though the temperature got a bit high at 62 degrees Celsius at the end of the discharge test. Moving to 15C and 20C discharge rates the the battery still handles quite well, but the real problem is that it gets way out of the safe operational zone with temperatures of 78-79 degrees. These temperatures are way too high for constant discharge of at 15C or 20C rates, though the battery should be able to handle well momentary peaks of up to 20C.

The performance of the 2S 7.4V 350 mAh Zippy 20C LiPo Battery in our tests:

– 337 mAh at 0.35A load (1C)
– 332 mAh at 1.75A load (5C)
– 329 mAh at 3.50A load (10C)
– 305 mAh at 5.25A load (15C)
– 275 mAh at 7.00A load (20C)


The 1.2V AA 2400 mAh NiMH Turnigy LSD batteries are NiMHs of the newer Low Self Discharge type that retain significantly more of their capacity over time as compared to the normal NiMH batteries that have faster self discharge. According to Hobby King selling these batteries they should not loose more than 30% of their charge in the course of a year when not being used. These Turnigy LSD batteries are rated with 2400 mAh typical capacity and not maximum capacity, though we are going to check if that claim holds true or not.

Official Specifications:

– Category: AA batteries
– Capacity: 2400mAH
– Voltage: 1.2V
– Chemistry: NiMH
– Weight: 29g
– Dimensions: 51x14mm

We started testing the 1.2V AA 2400 mAh NiMH Turnigy LSD batteries with initial discharge to see what capacity they still had when we got our order from the online store in order to check their LSD capabilities. The capacity provided was about 60-65% of their typical rated capacity, though we don’t know when they were produced, but according to the claim of about 30% discharge per year they should be made about a year ago. The minimum initial discharge capacity we got was 1505 mAh and the maximum one 1543 mAh from four different batteries that we tested with.


The 1.2V AA 2400 mAh NiMH Turnigy LSD batteries have managed to provide very good results in our tests providing 2380 mAh with a discharge rate of 0.2A that we tested as a minimum discharge rate and that is pretty good. The batteries also handle very well under high current constant discharge loads of 2A that was the maximum we tested with providing 1240 mAh. We do our tests of NiMH batteries at a constant current discharge rates of 0.2A, 0.5A, 1A and 2A or with about twice higher as compared to what we test Alkaline batteries at due to the fact that NiMH batteries tend to provide higher capacity and are able to handle better higher current draw.

The performance of the 1.2V AA 2400 mAh NiMH Turnigy LSD Batteries in our tests:

– 2380 mAh at 0.2A load
– 2149 mAh at 0.5A load
– 2139 mAh at 1A load
– 1240 mAh at 2A load

– 2.920 Wh at 0.2A load
– 2.553 Wh at 0.5A load
– 2.402 Wh at 1A load
– 1.270 Wh at 2A load

In overall the 1.2V AA 2400 mAh NiMH Turnigy LSD batteries are performing very well and are available at a very good price online, though the shipping cost makes it worthwhile only if ordering more batteries as these are only being sold online and shipped from Asia.