Battle Born Charging

[BFL13]

This might answer some recent questions.

The table is not accurate wrt to the BB comments--don't go by it by the table itself. Wade through the questions and answers to get the true picture. Takes a while to go through the comments, but that's where the info is.

https://battlebornbatteries.com/charger-compatibility-table/

[steveh27]

Just checked my 2 100AH Lifepo4 batteries voltage. I've stored them inside for 4 months now. 13.33 and 13.39 volts. That seems good to leave them alone for the long storage time I still have ahead.

[Itinerant1]

3 tons wrote:

Just got my 200a/hr Lifepo4 today, so this info is very timely indeed !!

Did you go with BB or another brand?

[Mobilesport]

Looked like a Crystal meth tweeker wired his battery up.
I really liked his Balmer monitor though.

[3_tons]

BFL13 wrote:
https://joana.ca/2019/09/01/new-lifepo4-battery-bank/

Here's a build your own version with photos of interest with comments on monitors and SOCs.

Oops, as was this one:

https://www.cruisersforum.com/forums/f166/trojan-lithium-drop-in-replacement-209665-3.html
.

Thanks, Both are interesting links...Makes one wonder how long before a programmable converter charger is made available - but (the cynic in me here - lol) this advance would likely work against the best interest of battery manufacturers.

Just got my 200a/hr Lifepo4 today, so this info is very timely indeed !!

[BFL13]

https://joana.ca/2019/09/01/new-lifepo4-battery-bank/

Here's a build your own version with photos of interest with comments on monitors and SOCs.

[Itinerant1]

From that link this sums it up.

"What seems to be misunderstood is that the BMS systems on most of these drop-ins are catastrophe level protection only, not a cycle life optimized BMS..."

[BFL13]

Itinerant1 wrote:
As can be seen after looking at enough of the LFP batteries specs (dropin) they are top balanced. Which is why they have 14.2-14.8 spread in the knee so their BMS can balance the cells in the pack, while also resetting the SOC capacity.

It's best if you have a programmable charger but it seems that the converters are like the dropin batteries and you get to pick your poison for charging, a one size fits all.

The BMS in the battery shouldn't be used as your first line of protection, that's why having programmable parameters in your charging source so it can protect first so if they fail the battery BMS can do it's job as the final line of protection and shutdown.

Really good discussion about all this here. Main idea being "drop in" also means drop in a matching charger. Lots of trouble with alternator charging the full Li (applies to boats and RVs) Of course in an RV you have the OEM converter as well as alternator and solar to deal with for matching Li specs.

https://www.cruisersforum.com/forums/f166/trojan-lithium-drop-in-replacement-209665-3.html

[Itinerant1]

As can be seen after looking at enough of the LFP batteries specs (dropin) they are top balanced. Which is why they have 14.2-14.8 spread in the knee so their BMS can balance the cells in the pack, while also resetting the SOC capacity.

It's best if you have a programmable charger but it seems that the converters are like the dropin batteries and you get to pick your poison for charging, a one size fits all.

The BMS in the battery shouldn't be used as your first line of protection, that's why having programmable parameters in your charging source so it can protect first so if they fail the battery BMS can do it's job as the final line of protection and shutdown.

[3_tons]

Not to mention a product name, but I inquired about a supposed Li charger brand in the context of an extended charging period and was told that the batteries BMS would guard against an overcharge scenario...But not all Lifepo4 batteries have the same voltage cut-off spec..In the case of a battery cut-off voltage higher than that ofthe charger output, the BMS will not be a sufficient safeguard to avoid overcharge..

The point here is that there is little convention on this issue, and a given charger should be matched with a given battery’s charge specs, and to understand that the BMS is not for controlling thenormal charging regiment. JMO - please feel free to comment!

[Mobilesport]

BFL13 wrote:
Trojan has one with the SOC indicator built in! Also note the charging rate is temp related so if it is under 73F you only use 56 amps. Also says capacity is down to 85% of rated at freezing temps, same as AGMs.

(BB says it wants .5C charging rate)

https://www.trojanbattery.com/pdf/datasheets/27_Lithium_12.8-110.pdf

Looks like its BMS provides over current protection too.

[BFL13]

Trojan has one with the SOC indicator built in! Also note the charging rate is temp related so if it is under 73F you only use 56 amps. Also says capacity is down to 85% of rated at freezing temps, same as AGMs.

(BB says it wants .5C charging rate)

https://www.trojanbattery.com/pdf/datasheets/27_Lithium_12.8-110.pdf

[BFL13]

deleted

[Mobilesport]

The Battleborn Voltage chart has 100% at 2 different places in the chart.
I assume the top one 14.4 volts is full charge when charging and 13.6 volt is a full battery at rest .

But it has been said that you must unhook all loads from the battery and then your supposed to be able to use this Battleborn chart.
The Li chart is supposed to be harder to read then the lead acid chart because the voltage range for the Li is much wider were the lead acid chart is simply 12.7 full 12.1 empty of what you can use
Easy with a lead acid chart when voltage at rest.

[MEXICOWANDERER]

Inverted on a new device at CEF number means 103% of the used amp hours must be returned to fully charge the battery. Impressive. The best AGM is around 91 CEF

[Mobilesport]

MEXICOWANDERER wrote:
Ask the mfr

C
E
F
Charge Efficency Factor

I found this
Charged Voltage: 14.0 9. Tail Current: 2% 10. Peukert Exponent: 1.1 11. Charge Efficiency Factor: 97% 12.
Link to more info
Charge efficiency factor