Jumping a lithium battery

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housedhs

Active member
Joined
Sep 12, 2017
Posts
29
Hey everyone...

I have a lithium battery connected to solar panels powering my RV cabin, and it ran completely out of power when the RV was in the shop (it was indoors for weeks, and the overhead fan probably drained the battery all the way).

I called tech support for the panels and charge controller, Renogy, who said the battery needs a jump before anything will work again. Until the battery is over a minimum charge, the charge controller will not engage and recharge it off the solar panels.

I have a black and decker jumper box, model J312B - could there be any issue using it to jump a lithium battery?

https://www.homedepot.com/p/BLACK-DECKER-300-Amp-Portable-Jump-Starter-J312B/205428102

I'm happy to provide further detail if necessary.

Thanks for helping me get my system back online... When it does work, it works great.
 
More details on your battery?

http://www.batteryreconditioninglab.com/how-to-recondition-lithium-ion-batteries/

 
Does your lithium battery(s) have a BMS (Battery Monitor System)?  Hopefully you have one.  If you really discharged the battery totally it may be ruined.  I would take a volt meter and check the battery voltage. 

What make/model of lithium battery do you have?

If the battery has an internal BMS and the BMS detected the battery was low enough to trigger the low voltage cut off, you may have to check with the battery mfg or owners manual to see how to reset the BMS, or if it automatically resets. 

Yes, you can put a 12V charger on the battery and charge it assuming the low voltage cutoff is reset.
 
Most modern chargers will shut down if the battery appears to be shorted, which usually means the battery voltage is so low that the charge amps exceed some max value set in the charger.  Thus Renology's advice to "jump" the battery.  It's not really a simple jump - you have to actually bring the state-of-charge (battery voltage) up enough to pass the chargers max amp limit test.  I'm doubtful that a simple jump device can do that, but it's probably worth a try.

Any lithium battery that is a plug-in replacement for a lead-acid 12v is going to have a built-in BMS - Battery Management System. Just how that may react to an attempt to jump it is hard to guess.  The usual method of bringing up the SOC to some minimally adequate voltage is to apply a trickle charge that slowly builds charge until the voltage reaches somewhere around 10.5-11.0v (for a 12v battery).  Might be more or less for a lithium, though.  If possible, contact the battery manufacturer for advice on the best way to do that.
 
This one is from a small company: Miller Tech Ultra Deep Cycle 80AH battery. It does have a BSM, and I don't believe it's drained 100%, going from the charge controller reading.
 
I would certainly try the Jumper Box.  It has no fancy controls to limit current flow.  It will charge until both batteries are close to the same voltage (state of charge).  Just be careful to not discharge the jumper far enough to damage it!  Hopefully, it gets the charge high enough to allow normal charging methods to work.
 
My question and answer.
Why haven't you call the battery Mfg, yet.

Or at least do a web search on this very question, based on your brand of battery?
 
There IS a general discussion available re the "sleeping" phenomenon for lithium batteries.  The recommended method for wakening them is the slow charging I suggested earlier in this topic.  Battery "jump" boosters are the opposite of slow and thus my doubt as to whether using one will work for this purpose, but it's probably worth a try if no other means is available. Personally, though, I would buy or borrow a modest  low-amp-rate charger and give it 24-48 hours to try to restore some charge.  The unknown is the built-in BMS in the LI battery - not sure how or if it will react once it shuts down.  Thus the suggestion to contact the battery manufacturer for advice.

https://batteryuniversity.com/learn/article/low_voltage_cut_off
 
Battery Universary:  https://batteryuniversity.com/learn/article/low_voltage_cut_off has some great, but usually general information.  I have learned quite a bit from reading the various sections there.

One very important "however".  Very little of the info there is directly related to the lithium batteries and the BMS (Battery Management Systems) used in RV's. 

The article in the link above doesn't to pertain to any lithium battery that I know of which are used in RV's and boats.

If anyone is going to install Lithium batteries, you want to have a remote battery monitor system to know how many amp hours (AH) have been taken out of the batteries and how many have been put back in. Also the battery monitor will show you at a glance your voltage.  Some BMS systems will also show you the voltage of each individual cell (4 LiFePO4 cells make up a 12V lithium battery at 3.2-3.3V per cell) as well as the temperature of the cell. 

It is far, far better and easier to NEVER get to the point of triggering the low voltage cut off than to recover from the cut off. 

Since you can discharge the LiFePO4 batteries to 80% discharged without damage it is easy to monitor the battery status and charge the battery before it becomes over discharged. 
 
The article in the link above doesn't to pertain to any lithium battery that I know of which are used in RV's and boats.
Not specifically, and I probably should have mentioned that.  However, all LI batteries have a built-in battery management system (BMS) with similar functions. The point is that LI batteries do not behave like traditional lead acid batteries.
 
I’m having this same issue. Did you ever find a portable solution to clear the bms reset? I have 2x250amh lithium batteries
Solar panels won’t engage until there is a charge on the battery
 
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