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If you fly micro helis such as the Solo Pro, Trex 100 and v911. You’ll quickly find that they each employ their own proprietary battery connector. What is an easy way to be able to hook these battery up to your programmable charger?

Simple. Take a clothespin and insert two tiny screws 5mm from each other. Then wire it up like the photo below to create a charging clip.

You can make more than one and wire them up to parallel charge. It’s easy to clip on and off and works great.

Pertinent Links:
RC Groups forum post

If you’ve read the datasheet put out by some of the battery manufacturers, you are aware of the break-in procedure for new LiPo. Basically, this amounts to being gentler on the new LiPo for 5 cycles or so.

I call it nicely waking the new cells from slumber. Because nobody likes a rude awakening. Proper LiPo care dictates that it should not be put away for storage in a fully discharge state, nor a fully charge state. Thus new LiPo will come from the manufacturer, resting at about ~3.8v.

So the first five cycles, I generally keep the discharge current at 3C or below. With 180mAh cells, this amounts not pulling more than 0.54A during the first five cycles.

Currently, I like to use my LiPo charger to break in the new cells. That way, I can see the discharge curve. and it also helps me determine the grade A cells from the lot.

Here’s a graph and you can see the chemistry working and waking up from storage. I used the same Miniaviation cell (MA1), charged and then discharged to storage (DS1 through DS5)* at 0.5A            *I accidentally overwrote my 3rd cycle (DS3), so I don’t have have the curve for that.

You can see that the cell performed better and better with each cycle. I included the first few discharge curves for the Hyperion 160mAh to illustrate this phenomenon happening with other LiPo cells as well.

Got a good deal on the 15c Miniaviation cells. These await connectors to be soldered on.

I finally got a hold of the new EFlite 150mAh 25c LiPo. I was curious about this cell because a Horizon Hobby employee said that the chemistry is better than their prior 1s cells. One person on the forum noticed that the head speed of their mSR X has a higher pitch, which suggest it was turning at a higher RPM than their Hyperion 160. That with the MSRP of $5.99 and Horizon Hobby listing it for a reasonable $3.99, it made me want to get one to put to the test. This proved to be difficult to find as it’s out of stock everywhere. The times when it came in stock at my local hobby shop, they marked it up at $9.99. This is the Hobbytown in Escondido. They also marked up the Hyperion 160mAh to $9.99 that can usually be found for $6.95 elsewhere.

New E-flite 150mAh LiPo

Anyways, finally found one at Discount Hobby Warehouse for $5.99. My curiousity got the best of me and I grab a single cell for testing. Now, bare in mind that the performance can vary from cell to cell. And I like to have at least three cells to give a better representation of it’s performance. But it’s interesting to see the result nonetheless.

It was nicely packaged. Weighs in at 4.4g. You can reduce that slightly if you remove the sticker because it wraps around the entire cell, with a little tab on one end. Anyways, make sure to click on the graph below to view it full size.

I need to grab a new order of Turnigy 160 and Turnigy Nano-Tech 160 from HobbyKing to see if those cells are really that bad or the ones I have are just worn. I also have some MiniAviation 180mAh coming from the UK. Will put that to the test once they arrive.

I was given a Xtreme Productions delrin main gear for the Solo Pro. So I took the weight differences between the v911, Solo Pro and Xtreme.

The v911 is the lightest, and very slightly thinner than the other two.

Here’s the weight of the stock v911 main shaft compared to the Solo Pro’s carbon fiber main shaft. In case you’re wondering, the Solo Pro main shaft is a drop in fit. No mods needed.