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DEKAs are significantly less expensive. Any thoughts on the difference?
DEKAs are significantly less expensive. Any thoughts on the difference?
Trojan Battery said:Generally, gel and AGM batteries have about 20% less capacity, cost about two times more, and have a shorter cycle life than comparable flooded lead acid batteries. However, Gel and AGM batteries do not need watering, are safer (no acid spilling out), can be placed in a variety of positions, have a slower self-discharge characteristic, and are more efficient in charging and discharging than flooded batteries (see table below). Gel batteries are more suitable for deep cycling applications whereas AGM batteries are more for light cycling and engine-starting applications.
Yep hogwash.... They will recharge faster, when new, but not 5X faster.. Deka's can take about 30-40% of capacity when new and floodeds can take about 25%.Sorry to resurrect an old thread, but a salesman at Batteries Plus is telling me that the group 31 x2 power AGM batteries (a rebranded Deka, right?) will charge back up 5x faster than a flooded cell of similar capacity, and discharge 3x slower. Is that a bunch of hogwash? I need to replace my aging batteries, and was really just wanting two 105ah basic old lead acid batteries. If his stats aren't just a bunch of hot air, that might be appealing... slower discharge, faster recharge.
If by timely you mean 2014...... (wink)A timely thread.
#1 Why do you have two house banks? That is likely issue number one.. One large banks is better for many reasons,I have two banks of 400ah AGMs. Last Summer the stbd side failed (sudden, drastic overheating). I replaced the two 4Ds with Lifelines. This week the same thing happened to the port side bank (Deka Intimidators). I was on the verge of ordering another set of Lifelines when I see Mainesail saying the FLAs are a better way to go.
The Trace 2512 was pretty advanced for its day but lacked direct on-battery temp sensing and was very often set up incorrectly by the end user for absorption voltage, float voltage and timer settings. Setting a proper float voltage for dockside charging with AGM's is critical. The optimal charging voltages for Deka are not the same as for Lifeline so one charger is not really the best case for a split bank. This is but one of many reasons why we don't usually split house banks..Sitting here at the dock, the batteries are charged by a Trace U2512SB inverter/charger. I've got 6 very old 75w solar panels that will be replaced by 100w Renogys going to 2 pwm controllers.
You can certainly mix AGM and flooded during charging PROVIDED they share the same absorption voltage and float voltage, otherwise this is sub optimal and not recommended. You should not discharge flooded and AGM batteries together so running the bank in parallel during discharging is not going to be optimal.I don't think I can mix the AGM and FLA batteries. So do I buy another $1100 set of AGMs, ditch the AGMs and get FLAs,
LFP batteries are considerably easier to destroy than lead acid batteries are. I have a guys 10K LFP bank in my shop right now that is a pile of useless scrap because it was not installed, charged and used correctly. This was a factory built system too not a DIY mistake. For a guy like me who specializes in LFP systems these stories are really not all that rare. They are rarer however on the internet, than they should be, because most folks won't admit to destroying thousands of dollars in cells or batteries in a public forum. This is not meant to come off as harsh sounding, but the reality is that if you can't mange lead acid batteries, and get maximum life out of them, then LFP is most likely not a good fit. For Lifeline's you should easily be able to exceed or achieve 7 years + for coastal and 3-5 for full time cruising.or bite the financial bullet and go to LiFePo?
There is really no such thing as "drop in LFP". That said nothing in lead, not even Firefly AGM's, can be compared to the cycle life you will get from a properly installed, charged and discharged LFP bank. To do it right, and many refuse to, you will almost always need to start from scratch on everything in your DC charging and discharging foundation. This means a charge bus, loads bus and the BMS to protect the bank. A factory made system is the best option for anyone not capable of a DIY LFP system but these are very expensive.. If you are not doing the labor or building the pack yourself (if you are not an EE or highly capable engineering type I would strongly advise against DIY) plan on about 7k -18K for a "legit" professionally LFP system. I use LFP on my own vessel so I am not saying this to discourage you, I am saying this to save you money in the long run. Course if you have deep pockets and can afford a multi thousand dollar "oops moment" then absolutely, go for it!The LiFePo option is appealing for the weight savings as well as more capacity, but I've been concerned about how much other stuff I'd have to replace. The price of the batteries alone is quite sobering.