SLI battery maintenance
Most of the battery discussion that takes place here obviously tends to focus on deep cycle, AGM, 6v, etc. I've learned a ton over the years and feel fairly knowledgeable when it comes to my house batteries. But I haven't given as much thought to my SLI batteries other than checking electrolyte level periodically.
The 2 SLI batteries in my truck are a bit over 6 years old. Based on that alone, they are likely nearing the end of their lives. When checking the electrolyte today I decided to also check the SG. All cells of both batteries were low. Average was 1.245. Lowest cells were 1.230.
Based on my deep cycle knowledge, I thought that desulfating them might buy them some extra time. By the way, they were starting the truck just fine before doing anything. I applied 16.2V at max 2A (roughly 3% of C for these batteries) for about an hour to each battery separately.
Afterwards, checked the SG again and it was nearly identical. Maybe a slight improvement in a few cells, never more that a .010 improvement though. What was different though is that the electrolyte was no longer clear. It had a brown tint, probably from millions of tiny rust particles suspended in the electrolyte. I've never seen this in my deep cycle batteries.
Anyway, I put them back in the truck and it starts just fine. Not sure though if what I did was a good idea. Probably not a big deal either way since they are likely due to be replaced soon anyway. Just wondering if anyone does ever desulfate their SLI batteries.
Obviously most car owners don't even know what desulfate means. They just drive until one day the car won't start and then they buy a new battery. But, in the interest of maximizing the life of an SLI, is it a good idea to desulfate or at least equalize them periodically? I'd love to hear what the battery experts think. As usual, thanks in advance!
The 2 SLI batteries in my truck are a bit over 6 years old. Based on that alone, they are likely nearing the end of their lives. When checking the electrolyte today I decided to also check the SG. All cells of both batteries were low. Average was 1.245. Lowest cells were 1.230.
Based on my deep cycle knowledge, I thought that desulfating them might buy them some extra time. By the way, they were starting the truck just fine before doing anything. I applied 16.2V at max 2A (roughly 3% of C for these batteries) for about an hour to each battery separately.
Afterwards, checked the SG again and it was nearly identical. Maybe a slight improvement in a few cells, never more that a .010 improvement though. What was different though is that the electrolyte was no longer clear. It had a brown tint, probably from millions of tiny rust particles suspended in the electrolyte. I've never seen this in my deep cycle batteries.
Anyway, I put them back in the truck and it starts just fine. Not sure though if what I did was a good idea. Probably not a big deal either way since they are likely due to be replaced soon anyway. Just wondering if anyone does ever desulfate their SLI batteries.
Obviously most car owners don't even know what desulfate means. They just drive until one day the car won't start and then they buy a new battery. But, in the interest of maximizing the life of an SLI, is it a good idea to desulfate or at least equalize them periodically? I'd love to hear what the battery experts think. As usual, thanks in advance!
