[roadkill]

here is a response an email i sent to trojan battery company

Hello,

We generally recommend a charging rate of about 10 to 13% of the system's amp-hr capacity.  This means that for a pair of T-105 (225 amp-hr), a good charging rate is about 20 to 30 amps (22.5 to 29.3 amps to be exact).  For deep cycle batteries, low and slow is good.  You can, if you wish, go higher in the current, up to 50% of the capacity.  Be aware that the higher you go in the charging rate, the more accurate your controller must be in order to prevent overcharging your batteries.

Please contact me if you need further assistance.

Best regards,

Jim Le
Technical Support Engineer
Trojan Battery Company
800-423-6569  Ext. 3045

it is funny they use the term "low and slow" yet recomend 20-30 amps also noted was that you can go as high as 50% charge rate as long as your controller was up to the task and at 10-13% that fall in with the finish charging in 10-12 hours

seems the important thing is to keep them full of water and dont let them over charge (voltage) and dont charge a frozen battery then they will last a long time

 

[epic]

This is what I've always been told about Deep Cycles. Dont leave them unattended for long periods of time with cheaper trickle battery chargers as they can overcharge the battery and cause a boil off. Its best to charge them on a 10-12 hour charge. Do not use fast, high rate, or boost chargers on deep cycle batteries. The electrolyte should never bubble violently while recharging. High charging currents only create heat and excess gas.

But I dont have any scientific data to support it, its just what I've been told.

 

[claimjumper]

How about using one of the solar chargers sold by Harbor Freight while you are troling? Will they provide enough charge to extend your battery use while you are troling?

 

[NeWcS]

Will they provide enough charge to extend your battery use while you are troling?

Not even close. You would have to have a hugh one for it to charge on the fly.


[me=Jay_In_Parker] [/me]

 

[Cutthroat]

This is what I've always been told about Deep Cycles.  Dont leave them unattended for long periods of time with cheaper trickle battery chargers as they can overcharge the battery and cause a boil off.  Its best to charge them on a 10-12 hour charge.  Do not use fast, high rate, or boost chargers on deep cycle batteries. The electrolyte should never bubble violently while recharging. High charging currents only create heat and excess gas.

But I dont have any scientific data to support it, its just what I've been told.

Trickle chargers are not the way to go, as they continue to apply current to the battery even when the cells are fully charged. Because not all cells in a given battery are equal, you can overcharge some cells, before the weaker cells in the battery are even fully charged. The best way to keep batteries topped is with a float charger after a short period on a higher amp charger. Float chargers provide a variable amount of current, rather than a constant "trickle" of current, and will (over time), insure that all cells in the battery are fully charged (without pushing any of the stronger cells over the top). If you put a battery on a float charger for a few days, it should last longer per charge and longer overall.

My strategy is to charge at 2-6 Amps until charged, then hook up the float charger, which can be left attached indefinitely with no negative effects (because it only applies charge when the battery will take it).

 

[jamiehughes]

i think that the t-105 batteries that roadkill had the company write him back on are quite a bit bigger than most automotive or standard rv batteries most deep cyle batteries are a bout 165 amp per hour rating not 225 hence maybe the difference in amp charging rates. i work in the automotive parts industry and we were always taught by the battery manufacturers that slower was always better as it made sure that the battery got a good strong charge, if charged at too high an amperage they can actually boil the acid out. but in the same note when on a vehicle the battery isnt charged at a very slow rate either. so how really knows?