spare battery wiring

[gordonv]

I have a trailer for my motorcycle. I have a LiFe (no off gases) battery from my GW (reversed polarity) and a plastic ammo box I'll be using as a battery box. I want to charge the battery while driving, and use it to provide light for the inside of my trailer.

I will plug the battery to the bike when I plug in the wiring for the trailer.

Question is: How should I wire it in?

Straight positive and negative.

Just add a diode, so the trailer wont power the bike.

A relay, something along the idea of a deep cycle battery in a camper (not that I know that one either).

I don't see the battery charging from the bike as being a problem. It should take the power as long as it needs some.

It also gives me a spare battery in case of trouble (along with some long power leads to reverse the polarity).

Thank you for any advise.

[WintrSol]

You may have better/safer results with something like this: https://www.etrailer.com/Accessories-and-Parts/Tekonsha/2024-07.html

[gordonv]

Thanks for the idea.

Looks like a 12V battery charger. For trailer batteries. I take it the trailer has a battery for electric brakes?

I just don't know if adding a non Lithium Iron battery charger is a good thing.

[WintrSol]

LiFe batteries are used as substitutes in motorcycles, and will charge OK with the bike's charging system, according to those that make and use them. You could look for a 12V-12V charger made for LiFe; never seen one, but I haven't searched, either. Using just a diode may not work, because the Voltage drop may preclude reaching full charge; maybe a Schottky diode would work?

My trailer uses a controller in the bike to activate the brakes, from the bike's power system; it uses a round connector, to get the needed contact count. I suppose you could put the driver in the trailer and power it from the battery in the trailer.

[WintrSol]

Article that may be useful: http://www.enerdrive.com.au/can-charge-lithium-battery-lead-acid-charger/

[Beardo]

Solar panel mounted on top of the trailer?

http://www.canadiantire.ca/en/pdp/coleman-20w-12v-solar-panel-battery-charger-0112023p.html#srp

[WintrSol]

Out of curiosity, I looked further into this, and, while you can 'get away' with charging from the alternator, the best choice would be a 12VDC-120VAC inverter and a LiFe charger, or one used by RC modelers with a 12V input.

[gordonv]

Solar panel mounted on top of the trailer?

http://www.canadiantire.ca/en/pdp/coleman-20w-12v-solar-panel-battery-charger-0112023p.html#srp

I have a 1W solar panel I would use on my car while parked during the summer while the MC was on the road.

Out of curiosity, I looked further into this, and, while you can 'get away' with charging from the alternator, the best choice would be a 12VDC-120VAC inverter and a LiFe charger, or one used by RC modelers with a 12V input.

I have a 75W cig power inverter.  I also have the LiFe charger. Would be fairly easy to add a cig outlet in the trailer, plug the inverter in with the LiFe charger plugged in and into the battery.

As for a diode, my thought was to stop power from going back into the mc battery. Since the LiFe battery should be close to full charge, it would just be a light load to maintain the battery. All lighting plugged into it would be LED. I have a white 5M strip for the inside lighting, and then was thinking of RGB for the underside of the trailer for light shows.

[murraypeart (bandit)]

I can help you with wiring the battery when we are in Merritt this weekend. I need to know how you are connecting the trailer wiring between the bike and trailer before I can tell you what is required.

[gordonv]

I was thinking of the plug for a battery charger or some heated gear. Male/female plug. I thinking I might have a 6' extension. Then I could just add another plug to the battery in the trailer reversed polarity, then plug the extension in each plug so it would be positive-positive/negative-negative.

There's a Lordco and a Can Tire there, might be a nice little project.