[Pamlicotraveler]

Here's the situation....

I have a v-berth battery used only for a lectra scan and a bow-thruster. It normally gets charged with an echo charger from the house battery bank. I am anchoring and have not been able to fully charge my house bank for a month or so, and so the V-berth battery is getting little or no echo charge and has dropped below 12-volts.

Will this solution work? I have a generator and am running the inverter. I want to use my Stanley Jump charger to somehow charge the v berth battery. If I just hook the charger up to the battery as if I'm jump starting, and leave it connected while I am also charging the jump-starter battery, will enough amps flow through to charge the v-berth battery?

I am afraid I am damaging the battery by having it below 12-volts for too long.

(using Stanley 450 AMP jump-starter)

 

[Maine Sail]

Here's the situation....

I have a v-berth battery used only for a lectra scan and a bow-thruster. It normally gets charged with an echo charger from the house battery bank. I am anchoring and have not been able to fully charge my house bank for a month or so, and so the V-berth battery is getting little or no echo charge and has dropped below 12-volts.

Will this solution work? I have a generator and am running the inverter. I want to use my Stanley Jump charger to somehow charge the v berth battery. If I just hook the charger up to the battery as if I'm jump starting, and leave it connected while I am also charging the jump-starter battery, will enough amps flow through to charge the v-berth battery?

I am afraid I am damaging the battery by having it below 12-volts for too long.

(using Stanley 450 AMP jump-starter)

In short a battery can not "charge" another battery. Some charge current will flow from one battery to the other when initially connected at differing voltages but once the voltages reach parity this charge current slows to the utterly useless mA range....

Sadly you have discovered why the Echo Charger is a poor fit for many bow banks. It is a voltage follower and needs to see high voltages in order to deliver its max rating of 15A, which can still be lacking especially with an Electro-scan. An ML-ACR is generally what I prefer but the cable runs get costly.....

In general, if the cable can be run from house bank to bow & meets the voltage drop requirements you aim for, I prefer to place the extra lead into the house bank and let it do everything.

To solve your issue in the short term get a small battery charger and run it when the generaotr is running via an extension cord...

 

[Pamlicotraveler]

Mainsail.....thanks for that explanation. Makes sense as that's what I am thinking I am seeing.

As for the smart charger, I have one and used it in the past but it will no longer charge this battery.
It gives an error code and says FULL.even though the voltage is below 12. I think it is too "smart." I wish I could dumb it down.

I don't believe this battery (AGM) has failed because it will still hold a decent voltage after I have been plugged in overnight.