Stupid question about Batteries

[dooma_Flatchy]

After a day on the lake I come in and hook up the charger on the batteries.(One for cranking and the other for trolling)
My question is- Do I need completely drain the batteries before charging them, (then I switch the charger over to maintain until next trip) or will repeatedly charging with 50 to 80 % of charge left in the batteries will cause a memory?

 

[Silvertip]

Re: Stupid question about Batteries

Draining a battery completely before you charge them is a bad practice. Charge them immediately after use regardless of the level of discharge. Why do you need to charge your starting battery. Isn't the charging system on the engine working??

 

[dooma_Flatchy]

Re: Stupid question about Batteries

I do a lot of run and gun fishing. The cranking battery hardly has time to charge while running, And I'm guess I'm a little gun shy, once I forgot to charge cranking battery and accidentally left the running lights on and drained my starting battery(was glad I had the trolling battery charged)

 

[jammer]

Re: Stupid question about Batteries

I do a lot of run and gun fishing. The cranking battery hardly has time to charge while running, And I'm guess I'm a little gun shy, once I forgot to charge cranking battery and accidentally left the running lights on and drained my starting battery(was glad I had the trolling battery charged)

Never fully discharge. I think you are taking the overly safe side to charging..but you will not have trouble at all with what you are doing. The crank battery doesn't need as much as you might think to charge.

 

[Barnacle_Bill]

Re: Stupid question about Batteries

Your batteries will last much longer if you recharge immediately (within 24hrs) after every use.

 

[dooma_Flatchy]

Re: Stupid question about Batteries

Thanks, and I am a little paranoid, I don't want to be stranded. I hate being towed in.

 

[drewpster]

Re: Stupid question about Batteries

I remember reading somewhere that battery memory is a problem mainly in dry cell batteries, not in wet cell. I cannot remember the specifics but wet cell batteries like to be topped off quickly. In fact leaving them discharged can damage wet cells due to electrolyte imbalance and sulfate corrosion.

 

[Boatist]

Re: Stupid question about Batteries

Wow everyone agrees WOW.
Discharging a starting battery below 80 percent or a deep cycle below 50 will do damage to the battery, So charge as soon as possible. Also charge at least every 2 month in summer, once a month or a battery maintainer even better. In cold temperatures still charge at least every 2 month.

I also charge or top off my batteries as soon as I get home. Put the charger on while we unload and clean fish. This ensures the battery is fully charged and replaces the power used to raise and lower outdrives and the power the Radio, GPS, depth finder used after you shut the engine off.

 

[Texasmark]

Re: Stupid question about Batteries

You are thinking about NiCad which have a memory. If you never fully discharge, before long they adjust to this level and the capacity is greatly reduced.

I think all of the guys that responded are full of it.................................................................

Ha Ha. I just had to do it since Boatist said what he did. Please forgive me!!!! Grin

Totally agree on wet cell.

For the record. I have a BB with 2 troll batt and 1 engine batt. The boat has been sitting for about a month and yesterday I decided to put the voltmeter on the batteries. The trolls were low (didn't look at engine batt) so I plugged in the built in charger. Came back with the voltmeter to see how much voltage the charger was putting out and when I got to the engine batt it was at 12.25, which to me is pretty low; 12.75 is a full (enough) charge for me.

2 things came of this which I had overlooked, ignored, or just didn't realize:

1. My built in charger only recharges my TM batteries, not all 3 like my son's does.

2. I don't run my engine enough to recharge my battery (either) so I need to periodically put the house charger on it.

Mark

 

[NgtvNrg]

Re: Stupid question about Batteries

The crank battery doesn't need as much as you might think to charge.

Will it do any harm to charge it every time?

 

[jammer]

Re: Stupid question about Batteries

Will it do any harm to charge it every time?

no it will not harm it