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I was just wondering if anyone has ever tried charging their trolling motor batteries with the car by hooking jumper cables to them. I have heard this is possible but not to sure. I am camping this weekend with no electric hook ups and don't wanna possibly have dead batteries out on the lake. It seems to me that the charge would be too fast or maybe the amps would be too much to where it would cause damage to the battery.
 

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I would think it would work but it would take a long time. I would hook up an inverter to the truck. Then you could plug in a charger.
 

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I was just wondering if anyone has ever tried charging their trolling motor batteries with the car by hooking jumper cables to them. I have heard this is possible but not to sure. I am camping this weekend with no electric hook ups and don't wanna possibly have dead batteries out on the lake. It seems to me that the charge would be too fast or maybe the amps would be too much to where it would cause damage to the battery.
I have a euHonda1000i you can borrow for your trip. I live in Tempe near ASU.
Let me know.
John
 

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I would think it would work but it would take a long time. I would hook up an inverter to the truck. Then you could plug in a charger.
+1-- this could be done but would charge batteries to fast meaning to many amps. causing possible damage to batteries and would cause alternator to run hotter than normal causing possible alternator damage-remember the alternator in a vechile is designed to recharge battery after starting and run accessories when vechile is running, it is not designed to be an all out battery charger.
 

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It will take a long,long time,trust me!!!!
 

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"I would hook up an inverter to the truck. Then you could plug in a charger."

This would be a huge waste. If you understand electricity you know that every time you change electricity there are losses, and in this scenario there would be a lot of losses.

1. You would be changing DC to AC via the inverter.
2. Pluging the Battery charger into the inverter would be taking the AC output of the inverter and converting it to DC (via recification) just to charge the battery.

DC to AC = Loss
AC back to DC = Loss

If you think it would take a long time going from your alt to a battery, the above process would be even worse.

Here is what I would do if I were you, I would buy a battery isolator. They sell them at car audio stores. I would run one terminal to the car battery, and then the other to a stationary post, then when and if you ever need to charge your battery you can just jump to the stationary post and charge from there.

No it will not ruin your alt. the rate at which the battery will get charged will be no greater than the output current of the alt. unless the battery is completely dead it will not act like that big of a load on your alt. and I guarantee it will not be a bigger load than say a high power amp, or a set of 100w halogens.
 

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Be careful,

Chargers are meant to put out 10 to 20 amps for a slow charge.

Car alternators can put out at least 100amps. It's made to maintain a charge not to do a slow charge. My alternator is 200 amps. I can run my ac, 6 KC lights stereo cranked, etc and the alternator just cranks it out.

A really discharged battery hooked up to a car alternator would put alot more current into the battery at a constant charge. It would look like a short. The alternator don't care it's just gonna crank out the current. Even the chargers have 50 amp for starting but it's pulsed for short periods of time.

I'd be afraid that putting that much power into the battery will really heat it up. Even possibly blowing it up because rapid charging will boil the sulfuric acid causing excess gas.

If you really want to use the alternator I'd go with the DC / AC conveter to the charging unit. This way it will regulate the current to the charging battery. It's not the ideal way to do it but it would be better in a pinch.

borrow the generator with the charging unit is IDEAL.

How about taking an extra fully charged battery with you as a backup.
 

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ive heard alternators are meant to maintain optimal battery voltage not actually fully charge them. thats why your not supposed to run your stereo or lights too long when the vehicle is off. ever notice when you drain your batteries, get a jump and let the alternator recharge the battery the alternator sometimes fails in the following weeks.
 

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"I would hook up an inverter to the truck. Then you could plug in a charger."

This would be a huge waste. If you understand electricity you know that every time you change electricity there are losses, and in this scenario there would be a lot of losses.

1. You would be changing DC to AC via the inverter.
2. Pluging the Battery charger into the inverter would be taking the AC output of the inverter and converting it to DC (via recification) just to charge the battery.

DC to AC = Loss
AC back to DC = Los
If you think it would take a long time going from your alt to a battery, the above process would be even worse.

Here is what I would do if I were you, I would buy a battery isolator. They sell them at car audio stores. I would run one terminal to the car battery, and then the other to a stationary post, then when and if you ever need to charge your battery you can just jump to the stationary post and charge from there.

No it will not ruin your alt. the rate at which the battery will get charged will be no greater than the output current of the alt. unless the battery is completely dead it will not act like that big of a load on your alt. and I guarantee it will not be a bigger load than say a high power amp, or a set of 100w halogens.
+1, this is how you charge your battery on an R.V. running down the road.
 
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