Battery Power for Stainz and Similar Locomotives

I have been searching for a battery to use for powering a Stainz (as have others); quite a challenge, given its diminutive size. But I finally scored. I bought one of these and it fits inside the boiler. Of course, you will have to remove the lead weight, but it does fit. Even better, when I tested it yesterday, it powered the loco pulling two cars for 1 hr 45 min, far exceeding my expectations (I would have been happy with 1 hour). There is plenty of room in the cab for a receiver and ESC, so a remote controlled battery powered Stainz is a distinct possibility. BTW, this battery also fits inside the cabin of the Elias tram locomotive (alongside the boiler).

You'll also need to buy a Li-PO charger; I bought this one; it's cheap and it works. I also bought some JST-HX 3S wire extensions for connecting to the charger.

My first victim will likely be this guy, which I wrote about a while back here:



The AAA NiMH batteries never gave enough run time (only about 40 min although they were rated at 1200 mAh, same as the Li-PO battery) and finally stopped accepting a charge. Once I get the new battery installed and connected I'll try to remember to post some photos.

I will be interested to see how you deal wih these Lipo batteries. They're something relatively unknown to me.

I've still got lead acid ones in some stock.

As I understand it, the chemistry of Li-PO cells are the same as Li-Ion; in fact, the voltage is identical. The main difference is Li-PO has a flexible (polymer) housing wheras Li-Ion has a rigid (metal) housing. Li-PO cells can therefore be almost any size and shape, although most I've seen are still roughly rectangular. The polymer housing does mean however one must use more care when charging a Li-PO battery.

The individual cells are best charged using a "balancing" charger, which simultaneously charges the cells in a battery in parallel. While you can charge cells in series, and some chargers do it this way, it is not recommended since a single cell could overcharge which could lead to bad consequences (fire, explosions, etc.). BTW, some folks advocate using balancing chargers for LI-Ion batteries as well. It is further recommended that one not charge a Li-PO battery unattended. Model airplane users typically remove the battery from the airplane to charge it and some use a "charging bag" which is intended to contain any shrapnel etc.

I'm not sure how credible the doomsday scenarios are, but that's what I've read. (There's a member at "that other forum" who is a strong proponent of the doomsday stuff. ) I figure a Stainz boiler is at least as strong as any charging bag and I use a balancing charger which I believe mitigates the hazards.

Anyway, I'm off to push the envelope (my own envelope, at least).