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Battery charger for Lithium battery.

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SolarExpress

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Jan 6, 2020
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I have 2 Renogy 12 volt lithium iron phosphate100AH batteries. Currently being charged by 400 watts from solar panels and also a Renogy 20 amp DC/DC charger. I am looking for recommendation of what "shore power"charger I can purchase to charge the 100ah lithium batteries when the vehicle is in storage out of the sun and not driven yet still using power from batteries. I have chargers for lead acid batteries and trickle chargers which I know will not work on lithium.
Looking for an inexpensive solution. Thanks
 
I would strongly recommend a Victron multi plus inverter/charger. It has enourmous flexibility/program ability, with the advantage of a seamless AC supply into the RV, when transferring on and off shore supply. Quite expensive, unless you also need an inverter in which case it becomes more competitive. Come as small as 500 w inverter, 20A charger, all the way up to 5000w/ 120A charger.
 
ijdrothman said:
Bought a duracell charger at Costco recently on sale for like $30. Does lithium and regular batteries.
Click to expand...

The only issue I see with some chargers is over voltage.
If that's kept in check, then about anything works, Watts are Watts, doesn't much matter where they come from.

For what it's worth,
I use a regulated power supplies, adjustable & less expensive than than some of the dedicated, high end chargers.
If you are the DIY type, discarded computer UPS systems have well regulated chargers, and they are easy to gang together for higher/faster charging.
 
Wellydex said:
I would strongly recommend a Victron multi plus inverter/charger.
Click to expand...
For storage?
You only need a trickle even for FLA.

Lithium are best stored at 30-50% charge. So for winter just discharge to 50% disconnect them and leave it for the winter - thats the best way to treat lithium (but not FLA).
 
Santa said:
this is very convisung...
Click to expand...
There's several types of lithium batteries and each have their own voltage parameters. For example, the nominal voltage for a Lithium Ion battery is 3.6v whereas the nominal voltage for a LiFePo4 is 3.3v. While the difference appears negligible, it's critical when charging the batteries.
 
Santa said:
Doesn't look like you can buy online
Click to expand...
Victron products appear sparse here in the USA. I've only come across a few, mostly on Amazon and on boating/yachting supply websites. I think Victron's manufacturing plant is in one of the twelve provinces of the Netherlands, maybe North Holland, South Holland, Drenthe, Limburg, Etc..

Oh, hey.... here we go: https://invertersrus.com/product/victron-ip65-12v15a/
 
Last edited:
I should add that some Lithium battery chargers use a blanket term to include LiFePO4 batteries as well. But there are some chargers that are specifically made to charge Lithium Ion batteries only. So check the specs before buying. I've checked the aforementioned Victron; it appears safe for LiFePO4 batteries; and after a long and exhaustive search for 'the one', that's the one I'll be buying.
 
JeepHammer said:
The only issue I see with some chargers is over voltage.
If that's kept in check, then about anything works, Watts are Watts, doesn't much matter where they come from.

For what it's worth,
I use a regulated power supplies, adjustable & less expensive than than some of the dedicated, high end chargers.
If you are the DIY type, discarded computer UPS systems have well regulated chargers, and they are easy to gang together for higher/faster charging.
Click to expand...
That's exactly what I've been doing. Because all that really matters is proper voltage and sufficient current.
 
Wellydex said:
I would strongly recommend a Victron multi plus inverter/charger. It has enourmous flexibility/program ability, with the advantage of a seamless AC supply into the RV, when transferring on and off shore supply. Quite expensive, unless you also need an inverter in which case it becomes more competitive. Come as small as 500 w inverter, 20A charger, all the way up to 5000w/ 120A charger.
Click to expand...
The Victron Multi-Plus line of inverter-chargers are impressive units that are well represented at least by their cost. I'd get one but I stubbornly insist on using component systems rather than integrated ones. That is, I have an inverter and a charger - if one goes down then it would be the only thing to repair or replace.
 
Last edited:
I know this is rather old thread but not sure the question was answered the way the op asked. LiFePO4 batteries want to be charged to 14.40v and only need to sit at that level for around 20 to 30 minutes thereafter as the current decays to a low level. No Float is necessary. Then its fully charged. There are a number of ways to accomplish this. I personally use a CC/CV power supply. And then shut it off after I notice the current has decayed to a low level. If I used a heavy current because I was in a hurry, I later will recharge using a 1 or 2 amp charge rate. Expert Power makes a 2 amp or a 5 amp LiFePO4 charger that is simple to use.

If there is a constant load on the battery, then I'd learn what that load amount is and put a power supply with a voltage in the range of 13.6v to 14.40v with a constant current set to just above your load level.
 
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