There is some significant discussion on this in another thread.
Here’s how I did the diode
Need to replace battery? What do you guys use?
- Thread starter LCMemphis
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Here’s how I did the diode
Agreed with 619toy. A diode is not going to do anything but potentially wear an AGM out faster. Needing to top off by plugging in an external charger is a good indication that the onboard charging system is not working as intended because it's not compatible with alternate chemistries.
Get a flooded for your main starting battery.
Use whatever chemistry you like for the aux battery, but it needs to be paired with a DC-DC charger that supports that chemistry.
The OEM TrueStart battery advertises a 7-year (84-month) warranty. I picked up a Costco Interstate 27F for $85+tax (+$15 core exchange).
I have put duralast gold in past older vehicles and had great results. A major factor there was the fact that locations to exchange are literally everywhere in case of need for warranty help.
But.. Toyota’s track record and as mentioned 84mo warranty eventually pushed me that direction.
But.. Toyota’s track record and as mentioned 84mo warranty eventually pushed me that direction.
Helps if you top them off every year with distilled water
It was maintained .. and probably would not had gone the 2.5 years if it wasn't ... OEM battery was total junk. The walmart batteries in my sport fisher are on 5 years for a comparison.
I think the original original batteries are still made by Panasonic? But dealership batteries are made by Interstate. But the Toyota branded batteries aren’t as good (specs-wise) as the best flooded batteries.
My closest Costco didn't have it. In fact, nor did the next closest 8 Costco locations. The Tire Center rep, told me the closest one was in North San Jose Santa Clara, so it was a 30 minute drive to pick it up.
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Wow. The suburbs of CA. 10 Costcos in 30 min drive.
LOL. There's 10 in a 30 minute driving radius surrounding Bellevue. San DIego is the same. (wow, I really must be bored). I was told that Costco in South San Francisco and Foster City are #1 and #3 busiest Costco Tire Centers. Both are 15 minutes driving from my place. #2 is somewhere in So Cal. I go to Costco... a lot.
Curios on whereabouts you live? Very hot area? Car not used regularly?
I always get 6-8 years from my batts whether stock Panasonic (absolutely the best but can't get in the states), Costco, "Toyota" badged from dealer. I never water these flooded led acids either as the smart alternators are very gentle on batts.
Can't say that about AGM. My experience with them is that they go 2-3 years before pooping out. Even the best Odyssey military grade metal jacket units and working with their techs. In my quest, I've learned they simply are not compatible even if marketing wants them to be for the reasons I already mentioned.
Now back to why your flooded Batts get such short lives? SoCal gets hot but not that hot. Some other locales like Arizona are just in another heat bracket and kills batts. AGMs won't tolerate that kind of weather either.
I'm in Atlanta and dealer found OEM battery was going and replaced with an interstate under warrant.
After living in Miami, Houston, Dallas, and Atlanta owning both cars and motorcycles I can safely say HEAT (and vibration from motorcycles) has killed every type of battery I've used in the last 3 decades (Oddysey, Optima, Name brand, rebranded, Lead acid, AGM). I just get the best quality with 5-7 year warranty battery I can at the best sale price (coupons, deals, whatever) and expect it to be replaced on warranty (prorated or otherwise).
While I believed some batteries went over 7 years, they didn't, I just put up with the symptoms of a failing battery for a long while until I bit the bullet and accepted the facts about vehicle batteries and heat.
YMMV,
Noah
After living in Miami, Houston, Dallas, and Atlanta owning both cars and motorcycles I can safely say HEAT (and vibration from motorcycles) has killed every type of battery I've used in the last 3 decades (Oddysey, Optima, Name brand, rebranded, Lead acid, AGM). I just get the best quality with 5-7 year warranty battery I can at the best sale price (coupons, deals, whatever) and expect it to be replaced on warranty (prorated or otherwise).
While I believed some batteries went over 7 years, they didn't, I just put up with the symptoms of a failing battery for a long while until I bit the bullet and accepted the facts about vehicle batteries and heat.
YMMV,
Noah
Here's a question - when you buy a flooded battery from Costco, Walmart or where ever, do you put the charger on it prior to installation, to make sure it's full up? So as to not overload the alternator or ?
you could but personally I never have, most places that sell batteries will rotate the stock so the oldest is out first and newest in stock to the back, helps keep batteries from getting stuck on the shelf for an extended period of time. just throw the battery in and send it
Agreed with @bigredmachine . Even in a lower state of charge, the smart alternator will know what to do and fully charge the battery in short time. So long as you're not installing and parking for an extended time.
Flooded lead acid batts also have relatively high internal resistance. Stock alternators can handle charging these just fine without ever overloading.
You didn't ask, but separately, overloading alternators can be a real thing when installing large aftermarket banks of AGM, and moreso lithium. Coming from the RV side which I frequent, which forums are loaded with battery/solar/install threads... These other types of batts have been known to overload alternators, regulators, and even accessory drive belts in other vehicle types because of the super high amperage (low resistance) demands they can put on the electrical system when in low states of charge.
Just wanted to chime in and recommend Deka for standard FLA batteries. I’m running one of their 100ah group 31 FLA right now.