trickle charging how long?

[motordavid]

Originally Posted by Ron07x5

What do you mean by floats along nicely and barely comes on again with charger in place? In place when and where?

Sorry it was unclear...I attach my Battery Tender to the 3 cars and 3 motorcycles, on a regular, rotating basis.

The time it takes to get 'to green' on any of those vehicles is a matter of how long any have 'sat' since I last drove/rode on an extended ride, and how long they have 'sat' with no BTender.

I may leave the BT on for a day, or days, on any given no low or no recent use vehicle, and it simply 'floats' along green for that period. Have never had a problem with extended use or attachment of the BT on any of our stuff, and all 3 Scoots and the Vette have an AGM batt.

That is what I meant by 'floating'.

I read your post of putting your low amp charger on in a couple weeks. I rarely let the cars go that long; they get much more frequent BT charging than a 'couple weeks'...the bikes sometimes get lost in the rotation, and might miss a couple weeks, but not the cars. We simply don't do enough regular long driving, so they get the BT regularly.

Should batts last longer/hold charge a long time? Sure, but they don't seem to these days. So, a BT or charger brand of choice, gets used regularly.
GL, mD

[Ron07x5]

Motordavid did not say I put charger on for two weeks, just 10 to 18 hours. Our use of x5 will be low miles often on level ground. I would like to know if we may deeply discharge the battery this way or not.

So my plan is to manually charge at 1 then 2 and 3 month intervals. If manual charging time increases in like linear pattern then I will know we can face deeply discharging the battery.

I know once a battery has less than 50 percent charge the voltage it provides drops. If lower voltages cause systems to get flaky then I want to avoid that..

Seems nobody really knows what the algorithm of battery charging is so I am left to discover in part by this experimental manual charging.

[motordavid]

Originally Posted by Ron07x5

Motordavid did not say I put charger on for two weeks, just 10 to 18 hours. Our use of x5 will be low miles often on level ground. I would like to know if we may deeply discharge the battery this way or not.

I meant, why wait to 'recharge' for two weeks? Unless it's not convenient, or you are running some kind of test. The low miles/rolling around town may or may not provide for keeping batt charged; in my experience with our cars, it does not. Or maybe it is OK, but hooking up our BT regularly is easy stuff, for 'prevention'.

So my plan is to manually charge at 1 then 2 and 3 month intervals. If manual charging time increases in like linear pattern then I will know we can face deeply discharging the battery.

Batts should go a month or more, and some surely do...my old 'company car' used to sit in airport parking lot(s) for 2 weeks straight, and I never trickle charges those car(s). That was then, this is now, with very different levels of electronics on cars, and maybe different/increased loads and charging req's.

I know once a battery has less than 50 percent charge the voltage it provides drops. If lower voltages cause systems to get flaky then I want to avoid that..

Seems nobody really knows what the algorithm of battery charging is so I am left to discover in part by this experimental manual charging.

Not exactly an EE or Batt xpert here; it is purely anecdotal, but my battery charging regime has worked on my Scoots for 30 yrs, and on our cars for 20 years. Good luck in your test regime, and curious to read an update.
BR, mD