Is there a easy way to transform 18v to 12v. I want to use my

An LM317T with a capacitor and resistor would do it.

>>1125429
depends, what's the current requirement for the fish finder?

power dissipation for a 317 is (Vin-Vout) x current draw, i'd try to keep it to less than 5watts with a heatsink

get a cheap buck converter off ebay (~$1 each)

>>1125404
http://www.ebay.com/itm/DC-DC-LM2596-power-Supply-Buck-Converter-step-down-module-GM-/262136732989
Don't forget to tune it with the adjustment screw, it doesn't automatically output 12V

File: Screenshot_20170203-095605.png (384KB, 1440x2560px) Image search: [Google]

384KB, 1440x2560px

.75A

Remove 2 of the 18650 cells from the battery. 3 wired in series will give 12v~

Typical battery will be made up of 10 18650 cells - 2 banks of 5 wired together in parallel to up the ampere-hour.

You need to be sure you understand which cells are wired in series and which are I'm parallel to realise which cells you need to remove.

I wouldn't recommend using resistors as you're just adding load to the battery unnecessarily and frankly, it's a lot of fucking about.

>>1125451
Well, I want the battery to also power my auger. So I don't want to rewire the batteries. I want to use them for dual purpose.

>>1125454

Call me a cynic but I'd have just bought an appropriate battery before going through this much hassle. You might have to go the route of reduction of voltage on the tool side of things. Again. More trouble.

Do you not have an old motorbike or car battery lying around and see crocodile clips? It's evident it doesn't really have to include integrity in your plan so just hack something together.

There's no simple way of retro fitting dual voltage like the flex volt batteries have as you'd have to switch contacts between voltages.

>>1125456
I haven't gone through anything. I just figured since I have three of these batteries maybe I could rig something simple up. I have a jerski battery I could use I just didn't wanted to keep weight to a minimum

>>1125446
Do you really have to drop it all the way to 12V? That specsheet says 10-17vDC.

>>1125471
I didn't see that. But even with a full battery it's a little over 20v

>>1125477
Do it anyway

Also how are youpowering the transducer

>>1125487
Yes. How do I know it won't overload the fish finder?

>>1125451
>>1125454
>>1125456
Dont rewire lithium batteries, you will break it.
And if you just remove the cells and charge them directly, you will just burn your house down.

Its not an efficient way to do it, but you could use a resistor in series with the fishfinder to drop the voltage. You did ask for an easy way though.

The reason I wanted to be able to hook the battery's up to a fish finder is because my drill powers my ice auger so instead of carrying different batteries I could just have one.

File: s-l1600.jpg (109KB, 800x800px) Image search: [Google]

109KB, 800x800px

just get one of these $2
http://www.ebay.com/itm/Buck-Step-down-LM2596-Power-Converter-Module-DC-4-0-40-to-1-3-37V-LED-Voltmeter-/161476280982?hash=item2598bc8296:g:-kcAAOSwyDxXhIGH

just plug it in
your fishfinder is probably smart enough to work fine

>>1125498
You're implying I'm as dumb as you. I rebuild batteries all the time for power tools and I don't relate to what you're saying.

>>1125927
>You're implying I'm as dumb as you.
That's unnecessary, and untrue, you shit.

I'm sure you rebuild non-lithium batteries, but I dont think you rebuild modern lithium batteries.
They have circuit boards with all kinds of protection like overcharging, over heating and whatever. They like to catch fire or explode and are protected against anything that might cause this. Repleasing cells; same-for-same is another thing though, shouldn't cause problems.

File: s-l1600.jpg (85KB, 800x575px) Image search: [Google]

85KB, 800x575px

Search for a buck converter on ebay.