Best Way to keep Batteries charged?
- Thread starter TexGX
- Start date
XJINTX
Explorer
I have my off-road trailer and my Miata ( driven rarely) both on trickle chargers (battery tender). Bought the cheapo ones at Harbor Freight and they seem to do the task fine. Trickle charge and shut off whne not needed. Small and effective!
I have a solar charger for the trailer but just do not want to leave it out and exposed all the time only use on the trail.
I have a solar charger for the trailer but just do not want to leave it out and exposed all the time only use on the trail.
Last edited:
JIMBO
Expedition Leader
:sombrero: YUP-
YUP, me too, a 60w hard panel that I can move anywhere for full sun exposure--works great
YUP, meto, sometimes I leave my jeep for up to 1 month (alone)/w a battery maintainer and all they do is provide millivolts for top end and help prevent sulfation from non-use-
I've been using the HF cheapie for 3 years-AOK-and Duracell maintener for the jeep
I'm expecting my '08 JKUR jeep battery to get over 5 years battery success !
:costumed-smiley-007:bike_rider: JIMBO
YUP, me too, a 60w hard panel that I can move anywhere for full sun exposure--works great
YUP, meto, sometimes I leave my jeep for up to 1 month (alone)/w a battery maintainer and all they do is provide millivolts for top end and help prevent sulfation from non-use-
I've been using the HF cheapie for 3 years-AOK-and Duracell maintener for the jeep
I'm expecting my '08 JKUR jeep battery to get over 5 years battery success !
:costumed-smiley-007:bike_rider: JIMBO
dwh
Tail-End Charlie
Pretty much any battery maintainer will work.
You want one that puts out enough amps to supply both the loads on the battery when the truck is sitting, as well as supply another extra amp or so to power up the solenoid that ties the batteries.
Pretty sure the NL will tie the batteries when the charge voltage rises on either side, so you should be able to hook the charger to either side and keep both sides topped up (but you should verify that before you do it).
Personally, I'd go with an 8 amp Battery MINDer:
http://www.amazon.com/BatteryMINDer...qid=1347113408&sr=8-2&keywords=battery+minder
You want one that puts out enough amps to supply both the loads on the battery when the truck is sitting, as well as supply another extra amp or so to power up the solenoid that ties the batteries.
Pretty sure the NL will tie the batteries when the charge voltage rises on either side, so you should be able to hook the charger to either side and keep both sides topped up (but you should verify that before you do it).
Personally, I'd go with an 8 amp Battery MINDer:
http://www.amazon.com/BatteryMINDer...qid=1347113408&sr=8-2&keywords=battery+minder
dwh
Tail-End Charlie
Yea...nah - that's what the brain is for.
I just reviewed the NL manuals for their split-charge relay:
http://www.nationalluna.com/Datasheets/Intel Solenoid Instructions.pdf
And their power pack:
http://www.nationalluna.com/Datasheets/BattBox Manual.pdf
I was wrong about connecting to both sides.
According to the manuals, the NL solenoid will tie the battery only when it senses charge voltage on the MAIN battery. (It was another isolator I was thinking of that senses both sides...C-Tek maybe...)
Apparently, the Power Pack uses that same isolator.
So, in the OP's case, the battery charger/maintainer would need to be connected to the MAIN battery - then the isolator would tie in the aux 5 minutes after it senses charging on the main side (just as it does when the engine is running).
Yea...nah - that's what the brain is for.
Good to know. Looking at the Battery Minder chart, even with temperature compensated control, it should out put 12.8-13.9v, which should be enough to keep the NLPP brain happy (12.7 minimum). Kind of moot for me, I embraced the whole "portable" thing and my NLPP only goes into the vehicle as needed. Nonetheless, it is nice to have options.
dwh
Tail-End Charlie
12.7v is the disconnect set point. The reconnect set point is 13.1v.
So, it ties the batteries when the main side reaches 13.1v and isolates them when the main side drops to 12.7.
But yea, the Battery MINDer 8a bulks to 14.4v (AGM) and 14.6v (FLA) so that's enough to activate the solenoid, and it floats at a minimum of 12.8v when battery temp is 120 degrees F, and floats at a higher voltage than that for any lower temps, so it should keep the solenoid activated at all times once the main battery gets up over 13.1v.
So, it ties the batteries when the main side reaches 13.1v and isolates them when the main side drops to 12.7.
But yea, the Battery MINDer 8a bulks to 14.4v (AGM) and 14.6v (FLA) so that's enough to activate the solenoid, and it floats at a minimum of 12.8v when battery temp is 120 degrees F, and floats at a higher voltage than that for any lower temps, so it should keep the solenoid activated at all times once the main battery gets up over 13.1v.
dwh
Tail-End Charlie
One thing to keep in mind, is that every time the Battery MINDer is unplugged from shore power - it might lose its settings and have to be re-programmed every time it's plugged in again. I dunno it if does or not, but quite a few digitally controlled battery chargers do lose their settings when unplugged.
dwh
Tail-End Charlie
2a might be enough - depends on how many amps of load are running when the truck is parked. If it's just the clock in the radio and the NL solenoid, it's probably enough. Barely.
But that's amps, there is also volts to consider. If the trickle charger only puts out say 12.6v, then it won't get the main battery to a high enough voltage to trigger the NL solenoid and tie the batteries.
The Battery MINDer is a multi-stage charger, so it will bulk the main battery up over 14v, which is plenty high to trigger the solenoid, and then both batteries will rise to that voltage and then the charger will back off and end up at a float stage voltage which will be high enough to keep the solenoid engaged - which will keep both batteries at the float voltage.
But that's amps, there is also volts to consider. If the trickle charger only puts out say 12.6v, then it won't get the main battery to a high enough voltage to trigger the NL solenoid and tie the batteries.
The Battery MINDer is a multi-stage charger, so it will bulk the main battery up over 14v, which is plenty high to trigger the solenoid, and then both batteries will rise to that voltage and then the charger will back off and end up at a float stage voltage which will be high enough to keep the solenoid engaged - which will keep both batteries at the float voltage.