My Random Eco(no)-Related Things Thread

[Stubby79]

This is a thread for me to drop random things I'm mucking around with in to, rather than start individual threads that will die of neglect as my attention waxes and wanes and jumps all over the place...

[Stubby79]

I had a good week of finding deals for projects. Not this week, mind you, but a week or two back...

Lithium Cells for $75: (Canadian)


Two 36V/15AH batteries. PO tried rebuilding it with a pre-built (but not wired to anything) unit from china...didn't work. Bad BMS. Old, brand-name cells are all good, holding full capacity; two of the parallel chunks (10S, 5P) of the chinese cells were bad...the opposite of what I was expecting. 90 good 3ah cells for $75, I'm not complaining.

Nice little generator for a whopping $35:


It's an old aircraft generator. 28V, 100A. Whoopidy doo? It's essentially a separately excited motor. You can control rpm or generator output via how much voltage you feed the field. It's nice and compact (6" diameter, 10" long), though a bit heavy (35lbs). All of that is nice, but what makes it particularly useful...it's rated for 10,000 rpm. One thing that's held me back from strapping an electric-assist motor to a car engine is that the one's I have are only good for ~5000rpm, and/or just too dang big. This can handle using 2:1 pulley ratio without blowing up...

A rolling motorcycle carcass for $50:


Which just happens to check off all the boxes of things I wasn't happy with on a previous purchase....cost less to boot. Drum brakes (that's a plus, IMHO), new(ish) after market rims, street-style forks, etc.
This is (now) the backbone of what I'm working on...

And...WTF?


It's...it's...probably a mistake.

It's a 3-cylinder diesel generator out of a light tower. Pretty low hours, if the hour meter is accurate. Sat around exposed for 2 years. But...I'm a sucker for a deal($100) and a project that involves either engines or making/storing electricity, and this is both...The engine is worth more, if it works, regardless if it ever puts out electricity again.

The generator was my first purchase that week...they just kept falling in my lap from there. Decent deals are hard to come by, living on an island...everyone asks top dollar for everything, unless they just want to get rid of it, which is the case with all of these.

I didn't need even one more project, now I've got several more. D'oh!

[freebeard]

Any predictions about how those will be employed?

[skyking]

nice little diesel !

[Stubby79]

Originally Posted by freebeard

Any predictions about how those will be employed?

Cells will go in to a larger pack I'll build some day...

Motor/Generator...for a hybrid project. Which one is the question.

Motorcycle will be the base for an electric bike.

Diesel engine/generator -- your guess is as good as mine! I'll consider it a good investment if I simply get it running well.

[Stubby79]

This is what I was building earlier this week:



Salvaged cells from power tools...all very healthy. Well, one pack wasn't, but it's not part of this larger one. 7S6P.

Capacity test came out right where it should be:



I had ordered an active balancer, but they sent me a 4S one rather than the 8S one I specifically paid for:



But it appears I don't need it. All the cells are staying within 0.02V throughout charge and discharge. Yes, they're brand-name, quality cells from the same manufacturer, but I expected some loss of capacity from some of them. Maybe it'll be more apparent under a heavier load. We'll find out...

[freebeard]

What's the [theoretical] output of the diesel generator?

High spec > diesel-electric hybrid.
Low spec > Home standby power.

[Stubby79]

The gen head is rated at 6kw. The engine is running at half it's potential speed/output, 1800rpm, for the gen head. Engine is rated at 23hp(17kw) @ 3600rpm, I believe.

[freebeard]

Overclock it like you stole it?

[Stubby79]

One could have fun with it...overreving it, screwing around with the peculiar - and simple - capacitive regulator. Sounds like an amusing experiment.