1984 FJ60 2FE
Due to parts availability and my circumstances, I currently have two AGM battery's and two alternators. An fj60 and an fj62 alternator based off this FJ60 Dual Alternator - https://forum.ih8mud.com/threads/fj60-dual-alternator.94294/
Things is, I don't want or need two alternators, its more equipment to maintain and if something breaks its more $$, belts are hard to find in the right size, and there's more specialty hardware involved that I don't have access to. But I really like having two batteries and I really don't want to spend the $$$ for a DC to DC charger. The price seems a bit steep for what it does, or maybe im just naive to the battery charging world and still have much to learn.
I DIGRESS.
So given that AGM battery's are picky and want to be charged individually, I was thinking I could just program an Arduino that detects which battery is at a lower voltage, then fires a relay to send 100% alternator charge to the lowest charging battery until that battery is at a 100% charge. After the initial battery is charged it will test to check which battery is at the lowest voltage and repeat the process. The only difference I can think of here is the frequency of charge time from the alternator is decreased. I will add that a charging priority would be given to the starting battery.
For example. We will refer to our starting battery as A and our auxiliary battery as B and a full battery is 12.7V. Say A is at 12.5V and B is at 12.6V; Because A is lower, A will get full alternator charging until it reaches 12.7V. Now say A is at 12.1V and B is at 11.9V; Battery A will get charging priority because it is our starting battery and its more important that battery A stays charged than B. A minimum Emergency threshold will be put in that overrides B's charging IF and ONLY IF A goes under say 50% charge capacity. As long as A is above 50% capacity then the Arduino will alternate which battery gets charging priority based off of which batter has a lower voltage. IF both battery's are at a FULL charge then charging will default to A and charge as if it were in a single battery configuration - until B drops say 20% below A (To avoid a rapid back and forth transfer of charge).
This is just a rough draft of how my charging algorithm would work. I know I can do it, I don't know if it's a healthy solution for the battery's and will promote longevity.
If you know anything about charging systems or battery's please leave some input! Thanks for reading.
Due to parts availability and my circumstances, I currently have two AGM battery's and two alternators. An fj60 and an fj62 alternator based off this FJ60 Dual Alternator - https://forum.ih8mud.com/threads/fj60-dual-alternator.94294/
Things is, I don't want or need two alternators, its more equipment to maintain and if something breaks its more $$, belts are hard to find in the right size, and there's more specialty hardware involved that I don't have access to. But I really like having two batteries and I really don't want to spend the $$$ for a DC to DC charger. The price seems a bit steep for what it does, or maybe im just naive to the battery charging world and still have much to learn.
I DIGRESS.
So given that AGM battery's are picky and want to be charged individually, I was thinking I could just program an Arduino that detects which battery is at a lower voltage, then fires a relay to send 100% alternator charge to the lowest charging battery until that battery is at a 100% charge. After the initial battery is charged it will test to check which battery is at the lowest voltage and repeat the process. The only difference I can think of here is the frequency of charge time from the alternator is decreased. I will add that a charging priority would be given to the starting battery.
For example. We will refer to our starting battery as A and our auxiliary battery as B and a full battery is 12.7V. Say A is at 12.5V and B is at 12.6V; Because A is lower, A will get full alternator charging until it reaches 12.7V. Now say A is at 12.1V and B is at 11.9V; Battery A will get charging priority because it is our starting battery and its more important that battery A stays charged than B. A minimum Emergency threshold will be put in that overrides B's charging IF and ONLY IF A goes under say 50% charge capacity. As long as A is above 50% capacity then the Arduino will alternate which battery gets charging priority based off of which batter has a lower voltage. IF both battery's are at a FULL charge then charging will default to A and charge as if it were in a single battery configuration - until B drops say 20% below A (To avoid a rapid back and forth transfer of charge).
This is just a rough draft of how my charging algorithm would work. I know I can do it, I don't know if it's a healthy solution for the battery's and will promote longevity.
If you know anything about charging systems or battery's please leave some input! Thanks for reading.