Question on IBS when trickle charging over a few days.

[JTdiRtyD]

Is this all stated by Jeep or is it a theory? I don't know the facts about IBS but I believe the IBS does not "count" how much current goes out vs in and instead when you start the vehicle it comes alive and measures battery voltage and charge current to know the approximate battery state of charge at that point in time. The amount of current out vs in is not the same as it takes a charge about 1.5X what you take out to charge to 100% and that will vary with battery type and age which the IBS is not aware of.

And another thing, some chargers are designed to read battery voltage, charging current and when to ramp charging up or down measured at the battery clamps and the factory charger cable resistance is taken under consideration. When you plug a charger into the trailer connector at the rear bumper your adding 15-20ft of unknown wire that goes who knows where. Some chargers may over or under charge due to the added resistance of the trailer wiring. With that said I have been connecting a 50w solar panel and MPPT charger to my trailer connector since I got my JT in 2021 because it doesn't get driven much and if parked for several weeks the battery may not be able to start the vehicle. The trailer connection has worked ok for me for charging but maybe not for everyone.

I just removed and deleted the aux battery last week and replaced the main battery with a 94 series Odyssey and when I measured my old batteries with a complex meter that reads internal resistance and other things, it claims the battery is still about 80% of new after 4 1/2 years. I suspect keeping it on the solar charger has extended its life quite a bit.

As I said, thats the simple version of battery monitors. From my research it actually uses voltage, current, and temp to determine battery health. My best educated guess is, it knows how many amps (current) go in and out, runs that against what the voltage is reading while taking ambient temp into consideration and makes a "smart guess" as to the health of the battery. The IBS then controls how much charge it thinks is needed. I have read that it wont actually charge until it detects battery state is under 80%, until then it's just maintaining, much like your DC-DC chargers operate.

DC-DC chargers operate in stages (the below is AI pull)

• Stage 1: Bulk (Constant Current): The charger delivers maximum current to rapidly charge the battery until a set voltage threshold is reached.
• Stage 2: Absorption (Constant Voltage): Once the target voltage is reached, the charger holds that voltage constant while gradually reducing the current (amperage) as the battery nears 100% capacity.
• Stage 3: Float (Maintenance): The voltage is reduced to a lower, safe level to maintain the battery at 100% capacity without overcharging it, ideal for long-term connection.

My guess is, if we use these stages, is it enters stage 1 once the battery drops below 80%, stage 2 from 80-100%, and then stage 3 once it reaches 100% and stays here until it drops back down below 80% in which it enters stage 1 again.

This is why I think remote starts often fail when its cold, because the IBS isnt good at keeping the battery at 100% when it's just short commutes (this has been talked about quite a bit on the forums, that short commutes don't fully charge the battery). It doesnt have long enough to keep it charged while in stage 3. So when the high current draw from a starter hits a battery thats close to that 80%, it's too much of a drop and the IBS thinks its a weak battery and cancels the start. Why cancel remote starts but wwork fine otherwise? I would assume theres systems in place to stop remote starts if XYZ don't match to prevent possibly stranding motorists, and those features aren't present with manual starts.

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[Blade1668]

As I said, thats the simple version of battery monitors. From my research it actually uses voltage, current, and temp to determine battery health. My best educated guess is, it knows how many amps (current) go in and out, runs that against what the voltage is reading while taking ambient temp into consideration and makes a "smart guess" as to the health of the battery. The IBS then controls how much charge it thinks is needed. I have read that it wont actually charge until it detects battery state is under 80%, until then it's just maintaining, much like your DC-DC chargers operate.

DC-DC chargers operate in stages (the below is AI pull)

• Stage 1: Bulk (Constant Current): The charger delivers maximum current to rapidly charge the battery until a set voltage threshold is reached.
• Stage 2: Absorption (Constant Voltage): Once the target voltage is reached, the charger holds that voltage constant while gradually reducing the current (amperage) as the battery nears 100% capacity.
• Stage 3: Float (Maintenance): The voltage is reduced to a lower, safe level to maintain the battery at 100% capacity without overcharging it, ideal for long-term connection.

My guess is, if we use these stages, is it enters stage 1 once the battery drops below 80%, stage 2 from 80-100%, and then stage 3 once it reaches 100% and stays here until it drops back down below 80% in which it enters stage 1 again.

This is why I think remote starts often fail when its cold, because the IBS isnt good at keeping the battery at 100% when it's just short commutes (this has been talked about quite a bit on the forums, that short commutes don't fully charge the battery). It doesnt have long enough to keep it charged while in stage 3. So when the high current draw from a starter hits a battery thats close to that 80%, it's too much of a drop and the IBS thinks its a weak battery and cancels the start. Why cancel remote starts but wwork fine otherwise? I would assume theres systems in place to stop remote starts if XYZ don't match to prevent possibly stranding motorists, and those features aren't present with manual starts.

Reading a few of your post is making me think I need to verify how my solar system is hooked up on starting battery system possibly. Especially since the battery failure I had last year and dealership repair.