Lithium Upgrade - Converter charger

As long as you can get the voltages set correctly, I see no problem...other than you may have to babysit it. Most Li's don't have an absorb phase, so be aware of that. And float is likely unnecessary too.

Be sure your solar controller abides by the rules too.

Progressive Dynamics told me that with my PD4635 converter charger and my 2 100AH Lifepo4 batteries I should push in the boost button to get the higher voltwge, It has worked well the few times I used it. I am not using it now.

Thank you guys for your responses!

I was just worried about how the converter will behave when putting the "Voltage Booster" before the battery. I understand that the converter determines the
charging stage (Float, bulk, etc) automatically by reading the battery voltage. However, with the "Voltage booster" in between, I have no idea what charging stage the converter will pick? What voltage will it read from it?

I guess I will have to test it... I was hoping someone had tried this.

Replacing the converter to a Lithium compatible one will cost me around $200. Instead, if this works, I will spend only $15 for the Voltage Booster... just trying to save some money.

Thank you,

Paul

pvelit wrote:
Instead, if this works, I will spend only $15 for the Voltage Booster... just trying to save some money.

You just spent a lot of money on those very nice batteries. Now is not the time to get cheap.

I echo what 2oldman says. Expensive batteries need a proper charging system. This is not the time to be cheap.

Ha,ha,ha...I am a curious guy and I like to see if things work... if they do, then, why not. However, I guess you guys are correct. I may just go and buy a new charging system... but I may buy the booster and try it anyway :)

Thank you all!

I'm not up on this stuff but I wonder why the booster wouldn't work.

I echo the sentiment. Get a charger that can be programmed appropriately. The LIFePO4's don't like float/absorb charges

ScottG,

Li are finicky about how they are charged. For example, they prefer to not be float charged. Lead acid on the hand love to be floated.

ScottG wrote:
I'm not up on this stuff but I wonder why the booster wouldn't work.

This question depends on what batteries you have?
drop in replacements or home built lithium cells.

Drop ins you can use anything you want to charge them. BMS controls all functions as to how they are charged LVD HVD LTD especially if we are talking about battleborns. Other brands do not have low temp disconnect. NEVER charge below freezing.

Since you have solar let the solar do its job on the highend and you can monitor any charger for the "bulk" for fast charging.

If you want to maximize cycle life end the charge at 13.6-13.7 for LIFEPO4 Lithiums don't like to be at 100% at all times they live much longer at 80% SOC even Tesla recommends this on their NMC batteries.


They don't mind 100% but not forever cell degradation happens at very low cell voltage and at very high cell voltage of their charge curve.

The advantage of Lithium specific chargers are high amps for fast charging and complete cutoff at the 14.4 level. You wont find this in a regular charger as the absorb, float and equalize are all functions lithium does not want or care about.

Again if its a battleborn the BMS will take care of everything for you without a thought of damaging the cells.

Also if you are hooking up to utilize the charging off your alternator disconnect the battery or buy the battery isolation manager. You will toast the alternator eventually as they weren't designed to run wide open all the time. you start your car alt is asked to replace the amps then goes to a sleep mode where as if lithium is involved it will ask for anything the alternator can put out amp wise. dramatically shortening its life.


Now if its a home built system without BMS you need to monitor the voltages per cell and don't go over 3.65v per cell. Victron LVD with bluetooth will handle the low voltage and you can cut the power anytime you like with the phone app. Solar charger must be programmed if you can't program your solar charger dont use with lithium. without a bms Morningstar is harder but works, victron is the easiest with a lithium charge alogorithium built in plug n play.

BMS's are coming online with ebay and aliexpress, battery hookup if you don't want to monitor your batteries basically turning it into a battleborn.


If you look at the charge curve of lithium they live happily between 12.0v and 13.3 once you go outside of that they either charge rapidly or fall rapidly if you go past 14.4 or under 10.6 those are the only times you risk doing damage to a lifepo4 cell whether its prismatic or cylindrical.