Towed Vehicle Battery Charging Interesting Idea

theoldwizard1 wrote:

Horsedoc wrote:
I just ran a fused 12 volt line from the MH to the battery of the toad. Is that not a good idea? Certainly easy and simple.

Simple, easy and INADEQUATE !

You will never fully charge the "house" battery this way.

Horsedoc, you are being misdirected (inadvertently I think). Your installation is perfectly adequate for a toad vehicle. Many thousands of towing setups operate like yours every day. OP is theorizing on how to maximize charge to depleted batteries, not maintaining already charged battery, which is all you need.

Nothing new... boating industry has used 3 stage voltage regulation long time..

http://www.balmar.net/balmar-technology/multi-stage-regulation/

But yeah with the ecu control im not sure how to do it..

But to get load of alt just use an external rectifier..

https://www.youtube.com/watch?v=3o_cWxAsyDI

https://store.alternatorparts.com/qf210-quicktifier-210-amp-external-bridge-rectifier.aspx

Depends on the situation. Charging at 11,000 watts my alternator equals (?) 44 250 watt angry solar panels. A six hour drive down here is minimum. What I am trying to convey is no one answer is the "right" answer for many folks.

We go weeks with 100% cloud cover, and campground receptacles are lucky if they yield 700-watts. During low demand hours.

The charging/towing driving scenario is an option not the main event.

The more rational options, the better.

theoldwizard1 wrote:

Horsedoc wrote:
I just ran a fused 12 volt line from the MH to the battery of the toad. Is that not a good idea? Certainly easy and simple.

Simple, easy and INADEQUATE !

You will never fully charge the "house" battery this way.

Why does the Towed vehicle battery need to be 'recharged' ?

The 12 volt direct line is plenty for virtually all towing conditions.

IMO fully recharging a large trailer house battery while driving is a bit overrated. Solar or generator at camp or solar on the road is the better solution.
JMHO

I'm spoiled. I have a 2/0 cable running from the remote rectifier to the L16's. The original alternator battery lug powers the chassis. Gotta find a tow dolly for the Spirit. No more flat towing. Nawww. I'm too lazy. Drive one or the other. Driving a train is too much of a hassle at my age.

i have a 10 amp version on the safari
to maintain the chassis batteries from the HOUSE batteries

the Idea is a trick L charge

the connections are under the front hatch between chassis and house fuse blocks

carries around 3 amps avg, but has a 10amp auto reset on the input side for protection

MEXICOWANDERER wrote:
What goes around in circles eating direct current can go around in circles making direct current. I mean one of the whiz bang WC Fields selling points of an EV is it charges the batteries going downhill.

The day a gasoline engine can compete with subsidized AC electrical power for cost of a recharge is the day I depart the test bench to play with with LEGGOS wearing a diaper.

"What'cha carrying?"

"A jumper pack"

"Why?"

"My EV ran out of charge and this here $99.95 miracle box says it's supposed to get me to the next charging station. HEY! DON'T LAUGH! It even comes with a handle"


I can see those late night TV ads as I write this...as easy as pushing a Tesla using a chain...

:)

What goes around in circles eating direct current can go around in circles making direct current. I mean one of the whiz bang WC Fields selling points of an EV is it charges the batteries going downhill.

The day a gasoline engine can compete with subsidized AC electrical power for cost of a recharge is the day I depart the test bench to play with with LEGOS while wearing a diaper.

"What'cha carrying?"

"A jumper pack"

"Why?"

"My EV ran out of charge and this here $99.95 miracle box says it's supposed to get me to the next charging station. HEY! DON'T LAUGH! It even comes with a handle"


I can see those late night TV ads as I write this...as easy as pushing a Tesla using a chain...

OK Mex. Cool idea. Now take it a step forward and figure out for those of us driving EV's how we can tow our EV's four down and charge while we tow them...without overcharging them and cooking a 5000 dollar battery. :)

MEXICOWANDERER wrote:

https://www.ebay.com/itm/DC-DC-Converter-10-12-15-20A-150-250-300-400-1200W-Step-up-Step-down-Buck-Boost/382219150784?hash=item58fe0965c0:m:mCHY1nLxgu47cYpdyd1LmDA
These critters boost voltage up. Way up. Send sixty volts through long long circuit

Then at the batteries, another type unit (same ad look down the list) will BUCK voltage down to whatever you set the potentiometer to.

MEXICOWANDERER wrote:
Here is a 55 volt max input voltage solar controller to sixty amperes capacity. Smart charging.

https://www.ebay.com/itm/NEW-20A-30A-60A-PMW-Solar-Panel-Charge-12V-24V-LCD-Battery-Regulator-Controller/132046821183?hash=item1ebe9a973f:m:mSp7lk-3EMgMQhbOaaXObyA

You have the formula ! (Not sure about the durability of that cheap Chinese solar charge controller.)

MEXICOWANDERER wrote:
Wheeeeee... your alternator becomes a SMART alternator (whoopee)