Why AGM Car Batteries Are The Future

[Mwittke5857]

I use a couple of LiFePo batteries for camping. They are perfect in the summer. But, they can't be charged below freezing, unless they are heated. I bought a heated one, and found out it could only be heated with a proprietary AC charger. One advantage of LiFePo batteries is that they can be discharged almost to zero without harm, while discharging a lead acid battery to near zero decreases its life quickly. The other big advantage is that they charge much faster.

For a vehicle applications, it would seem to be easy to warm it up in the engine compartment, and then start charging, as long as the BMS (Battery Management System) won't allow charging until the battery is above freezing. That would be a nice option on a Bronco Sport. LiFePo batteries also need to be charged at a higher voltage than AGMs or flooded. Without modifying the charging voltages, I'm not sure you'd get the full capacity of the battery.

I'd look into Dakota lithiums, they do not require heating nor higher voltages (??) to charge them

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[sajohnson]

We have a couple Lion Energy 12v/105Ah LFP batteries in parallel that we use for coach batteries in our RV. It's possible that there have been significant advances made since we bought them, but as far as I know -- while they have some great advantages over lead-acid -- they still have significant limitations.

LFP battery mfrs & vendors will gush about how they are "plug & play dude!" Not quite:

* They cannot be discharged below ~0*F.
* They cannot be charged below~32*F.
* For that reason, some source of heat is necessary.
* Their performance gradually decreases as those limits are reached.
* IOW, the specified output and charging rate is only available at ~72*F.
* The vast majority have lame little 6MM or 8MM terminals that are very weak.
* Most LFP batteries are not a standard automotive size or terminal type.
* New hold-down hardware must be fabricated.
* LFP batteries should be charged at ~14.6V, that requires a "DC-DC" charger.
* A DC-DC charger controls both the charging voltage and current.
* If a LFP is connected directly to the alternator (the stock setup), it may be fried.
* Voltage is not a reliable indicator of SOC, because it stays flat to ~10% SOC.
* Therefore, battery monitor with shunt is required.

There are hundreds of sources for lithium batteries. Some are OK, many are not.

I just scanned the Dakota website and found this:

"DL+ 12v 135Ah Dual Purpose 1000CCA Starter Battery" with heater:
https://dakotalithium.com/product/dl-plus-12v-135ah-dual-purpose-1000cca-starter-car-truck-battery-plus-deep-cycle-performance/

As with most LFP batteries, it does not have standard top-post automotive terminals.

Also, the website says "pre-order". That may be OK, but it often indicates a start-up that is trying to get the money up front to have a product made. An established company would generally have no need to take pre-orders.

Don't get me wrong, LFP batteries have a lot going for them, and they can be made to work as cranking batteries in most (moderate temp) applications, but most mfrs recommend against using them as starting batteries -- likely because the BMS limits output current to a level below what many starters pull.

 

[Dude]

Yes but both Antigravity and Dakota Lithium (which incorporate a BMS) automotive batteries in the H6 Group 48 size state they can be used if the user verifies specs before installing in a Bronco Sport

See earlier posts #6 and #22

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