Keep alive alterrnative

[RR_Mel]

Greg is correct about Lithium batteries taking up space!  I went to Lithium LIR2032 coin batteries for my cabooses and old time Overton coaches for the LED lighting.

 

Charging is also a problem with Lithium batteries, even a slight over charge dings a coin cell.  It took three tries but I have a good working Lithium battery system.  This is one of my MDC Overton coaches with my Lithium powered LEDs.

 

 

 

 

 

I use latching reed switches under the roof to turn the LEDs on and off with a magnetic wand.

 

The LIR2032 battery will support the LED lighting for 8 hours without rail power.  The TP4056 charge board will charge a fully discharged coin cell in one hour from rail power at less than 20ma max per car.  Static (float) current draw from the rails is less then 5ma per car with the LEDs turned on.

 

 

Mel

 

Modeling the early to mid 1950s SP in HO scale since 1951

 

My Model Railroad   

http://melvineperry.blogspot.com/

 

Bakersfield, California

 

I'm beginning to realize that aging is not for wimps.

[hon30critter]

ndbprr:

As Greg suggests, watch batteries have some limitations. Lithium batteries would work but I question why a manufacturer would spend the time designing a battery powered keep alive system when they could invest those resources designing dead rail systems instead. Perhaps, once dead rail has been sorted out, the technology could be used to design a keep alive but if I was a manufacturer I would be spending my money on dead rail first.

Dave

[gregc]

not sure what you mean by the "amperage issues"?

I believe capacitors or better yet, super-caps would provide sufficient current for a second or so in a minimum of space.   (i.e. better energy density).  They also require some circuitry which is a diode and resistor.

while batteries could be used, I believe they would occupy more space and require an additional charging circuit. 

I don't believe watch batteries can provide sufficient currrent and you would need several (8) to provide 12V and watch batteries are not rechargable.

[ndbprr]

As I understand the technology it is basically a capcitance discharge system for when the power from the rails is not connecting to the decoder. Wouldn't a lithium ion or watch battery do the same thing without the amperage issues?