How to choose the right lipo battery

[matthewsmith]

I hope you'll be able to help.

Like alot of people I'm looking to change to using lipos. I've read alot about how good they are and how to calculate the discharge rate, etc.

But the question I have is how do you choose which lipo to replace current NiMH?

As always any help will be greatly appreciated.

Cheers

[Gaffa]

Re: How to choose the right lipo battery

Go for the highest CONTINUOUS C ratings batteries. Don't worry about the burst ratings.

Higher mAh = bigger battery.

My 2100mAh 7.4v lipo's are the same size (well just a tad thicker) than an 8.4v mini.

I'm going to be using the above to replace my mini batteries, 7.4v 3000mAh 25C plus to replace my 8.4 large's, and 11.1v batteries to replace my 9.6v large.

I currently have 2 x 7.4v 1600mAh 25C batteries that I use in my MP5's, and 2 x 2100mAh 25C batteries - one of which goes in the front end of my L85A1 and the other I use in my Masada - although I'll be upgrading to a 11.1v for some guns that take 9.6v mini's...

(After hours of searching I finally found two! sources that sell 11.1v 2000mAh or slightly higher, batteries (not sure on C rating) that have the same dimensions as the 9.6v mini! - Win!)

[jfox61]

Re: How to choose the right lipo battery

Pretty much everything Gaffa says but one thing to be mindful of is that a 7.4V Li Po is about as powerful as a 9.6VNi Mh so make sure the guns internals can take that. Most can but it becomes more critical when using the 11.1V batteries

[B.E.N.]

Re: How to choose the right lipo battery

Strangely enough, I just had an email conversation with a well respected battery manufacturer regarding LiPo batteries... Here's his reply:

LiPo and Li-Ion batteries are usually perfectly safe as long as they are not crushed or mechanically damaged. In which case they can explode or catch fire.

In saying that, they can also explode or catch fire if they are charged incorrectly. All good manufactures such as ourselves incorporate a safety board inside that:

> Distributes the charge to each cell individually

> Protects the pack against short-circuit or wrong polarity

> Ensures that each cell is within its own safety limits (not too high or too deeply discharged)

There are many imported Chinese packs that have nearly no safety built-in and so it is down to the user to ensure that the correct external balancers and intelligent chargers are used.

We supply a Li-Ion charger to a company that makes metal detectors for finding land mines in war areas. They told me that just for fun they deliberately short circuited a fully charged Li-Ion pack in a controlled environment to see what would happen. They claimed that the pack exploded with a larger force than the land mines they were trying to find.

I know of someone who gutted his porch area with fire when he selected the wrong setting on his charger with a LiPo pack.

As I understand it, it was a laptop LiPo battery that burned down a big area of the Los Angeles Airport.

I know for sure that 2 large LiPo factories in China burned to the ground in the last few years and BMZ, Europe's largest pack maker suffered huge loss when fire tore through their factory. See the links below:

http://www.chinapost.com.tw/business...a-suspends.htm

http://www.eetimes.com/news/latest/s...leID=210200231

[Fizzy]

Re: How to choose the right lipo battery

Any Ni-Mh pack can also explode if charged incorrectly or is damaged. They also give off toxic gas when they do go so can be more dangerous than a lipo

[jfox61]

Re: How to choose the right lipo battery

Hence aas thay say a charger with balancer and auto cut off to ensure safe discharge levels. As fizzy says, and to expand, any battery is dangerous if abused. I have used chinese batteries with my charger for 3 years now and no ill effects at all. thats because they are used with a good charger and are charged in a safe environment. And that goes for any of my batteries not just Li Po's