Another Battery: question jumping a battery

Blue Thunder · 09-27-2016, 07:00 AM

Quote:

Originally Posted by Descant

Many boats have multiple batteries, and much heavier duty than a car. A cheap jump pack may not have the "oomph" that a "professional" grade has. I had dead batteries and a fully charged box. No go. Borrowed the heavy duty one from the Marina and started right up. Now I have a top of the line that also can run AC. Being well prepared, now I never need it, but it also blows toys up faster. and I don't need a separate air pump. There is a separate thread about jump packs and alternatives.

I have a similar jump pack. Air compressor for the toys (and the boat trailer tire!) A built in light and the best feature is a switch that you activate AFTER making the connection to the battery you are jumping. This practically eliminates the spark possibility. 500 amps of jumping power. I've never needed it to jump my own boat, but it has helped countless others.

BT

Downeast · 09-28-2016, 08:12 PM

Yes no special jump pack is needed.

Once you get yourself going, get to a charger as soon as you can for the purpose of your alternator is merely to sustain / maintain.

The 'more dead' the battery, the harder the engine has to turn your alternator as it is (alternator) wanting to put out some pretty high current to get the battery back up there... thus an unnecessary strain on the alternator.

Heat builds in the alternator and the high charge rate builds heat in the battery.

Heat is the killer. No good.

Battery will gas more violently. In certain instance when equalizing is the purpose, even then excessive heat should be avoided.

In an ideal situation, and most all do not do this, is to jump you car, get going where you have to be, and charge with a charger asap at a more relaxed rate such as 10 amps or less.

(safely a max of 20% of combined AH capacity -- [roughly 24-31 series batts are about 75-130 AH]

so basically charging at a max rate of 20% (10-15amps) will be ok , additionally this is why most chargers on the shelf average 10 amps. and 20amps on occasion if you look hard enough)

As per the former question about storage:

Do NOT top off water before battery is fully charged and NEVER allow plates to become visible.

Charge thoroughly and Disconnect the negative, tape up terminals.

Years and Years of service if batteries don't have a chance to sulfate

The Following User Says Thank You to Blue Thunder For This Useful Post:
thinkxingu (09-27-2016)

09-28-2016, 08:12 PM	#2
Downeast Senior Member Join Date: May 2015 Posts: 104 Thanks: 1 Thanked 39 Times in 22 Posts	Yes no special jump pack is needed. Once you get yourself going, get to a charger as soon as you can for the purpose of your alternator is merely to sustain / maintain. The 'more dead' the battery, the harder the engine has to turn your alternator as it is (alternator) wanting to put out some pretty high current to get the battery back up there... thus an unnecessary strain on the alternator. Heat builds in the alternator and the high charge rate builds heat in the battery. Heat is the killer. No good. Battery will gas more violently. In certain instance when equalizing is the purpose, even then excessive heat should be avoided. In an ideal situation, and most all do not do this, is to jump you car, get going where you have to be, and charge with a charger asap at a more relaxed rate such as 10 amps or less. (safely a max of 20% of combined AH capacity -- [roughly 24-31 series batts are about 75-130 AH] so basically charging at a max rate of 20% (10-15amps) will be ok , additionally this is why most chargers on the shelf average 10 amps. and 20amps on occasion if you look hard enough) As per the former question about storage: Do NOT top off water before battery is fully charged and NEVER allow plates to become visible. Charge thoroughly and Disconnect the negative, tape up terminals. Years and Years of service if batteries don't have a chance to sulfate