Lithium Polymer batteries are the latest in hobby battery technology. These batteries pack a high power punch with great power density, high discharge rate and no memory effect. Over the past several years, the price of LiPo batteries has come down significantly. A battery that cost $75 two years ago, now costs ~$20.
In this review, we will be taking a look at the “Blue Lipo” brand of Lipo battery, which is carried by hobbypartz.com. I have been using “Blue LiPo” batteries for about 6 months now and have gathered enough data to present this review.
To start us out, lets review some of the basics about LiPo batteries…
Here are some of the basics regarding LiPo battery specifications.
Each cell in the battery has a nominal, loaded voltage of 3.7 volts. A LiPo cell can be permanently damaged if allowed to be discharged below 3.0 volts or charged above 4.235 volts.
A Lithium Polymer (LiPo) battery pack may contain one or more cells. A serially wired battery pack may contain one to six cells with pack voltage of 3.7v to 22.2v, respectively. A battery pack may also be wired with a combination of serial and parallel cells to achieve the voltage and capacity needs of a specific application
LiPo battery pack capacity is measured in terms of mAH which stands for milli-amp hours. Discharge rate is described in terms of “NC” where “N” is a multiplier value and “C” is the capacity of the pack. Typical discharge rates include: 5C, 10C, 15C, 20C, 25C and 30C. If a battery has 1000 mAh of capacity and is rated with a 15C discharge rate, then it can continuously discharge at 15 Amps until it runs out of juice. The discharge rate is also described in terms of instantaneous and continuous rate. Be sure to check the manufacturers specification for a particular battery. Most airsoft guns require at least a continuous 20C discharge rate.
LiPo batteries are finding applications in more and more products. Many of the products that LiPo’s are making great in roads into include radio control cars, helicopters, airplanes, boats and electric airsoft guns.
There are still some safety issues with LiPo batteries that are being worked out, which is one reason why they have not been put into more general consumer products. Always charge and store LiPo batteries in a fire and explosion proof container. Never store a LiPo battery in a car or another location that can become hot. There are other safety rules you should follow that are provided by the manufacturer.
Review of the Blue LiPo branded battery
Ordering from hobbypartz.com is pretty easy. It is a typical online store that uses the Yahoo backend.
I have made 3 separate orders from hobbypartz.com and each time, I have been pleased with the quality of the packaging of the products.
When charging a LiPo battery, you must use a charger that is specifically designed for LiPo batteries. Always charge your LiPo in a fireproof LiPo bag or in a steel container to avoid risks of fire or explosion. If you are looking for a great LiPo/NiMH/NiCd charger, then take a look at my review of the Dynam DC6 charger. You should only charge a multi-cell LiPo battery with a charger that can balance the cells. Balancing is critical as it keeps the voltage and charge capacity at the same level for all of the cells in a pack.
I use Blue LiPo batteries in my airsoft guns. I have several 7.4v Blue LiPo’s and one 11.1v LiPo. All of the batteries perform very well and I can make it through an entire day of airsofting on approximately 25% of the capacity of a single battery.
Tracking the number of charges
In order to track the number of times that I have charged each battery, I make a small mark on the battery with a Sharpy marker. This provides a simple yet effective method of determining the lifespan of the battery. So far, I have charged and used each battery 5 times. I typically use each battery every other game.
The Blue LiPo battery comes with a large, high-current connector that is typical of RC toys such as cars, helicopters and planes. Unfortunately, it is quite large and does not fit within the tight confines of an airsoft guns battery compartment.
Because of the space constraints within the gun, I have converted all of my airsoft guns and battery packs to the “deans” connector. The modification requires a good soldering iron, some patience and a deans connector. Remember that the battery is always a female connector and the male connector goes on the guns wiring harness. Also, always work on a single battery wire at a time. Never cut through both battery wires are the same time as you are likely to short the wires and can permanently damage the battery, or cause a fire or explosion. Just be careful and you should be fine…
Performance in the field
I currently take 4 LiPos with me to each game; 3 Blue LiPo brand and one FireFox brand.
I started playing airsoft using a Firefox brand, 11.1v LiPo. After some research I have decided to back off to 7.4v LiPo’s in order to reduce wear on the AEG motor and mech-box. The 11.1v LiPo provides approximately 20% increase in rate of fire over the 7.4v LiPo. If you are a “spray and pray” type of airsofter, then the reduction in rate of fire might affect your game. If you have the moxie to aim a little more and work on your stealth, then the 7.4v LiPo provides a fine rate of fire in my opinion. I don’t really use my FireFox LiPo battery anymore. I have never had a problem with it, but since it is an 11.1v pack, it is now an emergency backup.
My other three batteries are Blue LiPo brand. I typically only need a single 1800 mAh battery to get through a game. I have the extra batteries in case there is a problem or someone on the team needs to borrow one.
In a 4 hour milsim airsoft game, I will typically use approximately 250 mAh worth of battery capacity. In a capture-the-flag style game I have found that I use about 350 – 400 mAh. When playing a night game and using tracer rounds, I have only seen an approximate 50 mAh increase in power consumption over a 5 hour period. My tracer unit is powered from the same battery that powers my airsoft gun motor.
How do I know how much capacity I am using? The LiPo charger that I have keeps a running tab of how many mAh it is charging back into the battery. This is an important feature to look for in a LiPo charger.
Overall, the Blue Lipo branded batteries work as I would expect. For the price and performance, they are unbeatable in my opinion. I now own 3 Blue LiPo brand batteries. I have two 1800 mAh packs and one 2200 mAh pack and I have never had a problem with any of the batteries. I will continue to purchase more of the Blue LiPo brand as I have the need. There are at least 4 people on my airsoft team using Blue LiPo batteries and everyone has had very positive results.
If you are looking for a great LiPo battery at a very reasonable price, give the Blue Lipo battery a try. When you order the battery from hobbypartz.com for the first time, be sure to order the fireproof “LiPo-Safe” bag as you can get it for only $6 when ordered with a battery.