Battery question - I think I dumb'd.

adri

adri

Well-known member
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My BMW G650GS wouldn't start today. Multimeter said the lithium battery had 1.8v. Fuuuuuuuu...n.

Now I'm wondering if it was the battery that failed me, or if I failed the battery... because in truth, I left stuff plugged in that I normally wouldn't. It went like this:

Lithium battery
--> Battery to SAE connector (battery tender pigtail)
--> SAE to USB adapter (with voltage display) - this one
--> Motorcycle Android Auto unit - similar to this

The SAE to USB adapter has a button on/off toggle switch. I hit it, the Android Auto unit dies immediately. I press it again, the unit boots up again. I assumed this meant that there is no power going through the SAE to USB adapter...

I'm guessing I was wrong and some power got through and I caused a little parasitic draw on my battery and killed it myself...

BUT, I wanted to ask because this same make/model of lithium battery has already failed on me in the past. A couple years ago, the manufacturer had me send in the original lithium battery for testing after it failed mid-ride. The manufacturer determined that it was a capacitor inside the battery that failed, through no fault of mine, and sent me a replacement battery.

Normally I always keep my bikes on tenders, but I had to lend a lithium battery charger to a customer and now being the hero has cost me lol.

What do you guys think, did I make stupid and kill my own battery, or did this thing off itself again?
 
adri said:
Multimeter said the lithium battery had 1.8v.
What do you guys think, did I make stupid and kill my own battery, or did this thing off itself again?
Click to expand...

What kind of battery is it? Brand and model?

Most Lithiums have algos in their Battery Management System (BMS) which will prevent damage from deep discharges, always keeping a minimum reserve charge inside regardless of what is drawing from it. So it *may* be recoverable without negatively affecting future battery life and performance.

Recharge and keep your fingers crossed!

Maybe install a dedicated USB socket on a switched power relay to prevent accidental discharges through parasitic draws? All it takes is one time to forget to hit the off button on that USB socket...
 
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I completely drained a new LI battery on my Husqvarna 250 by leaving the key on.

I bought a(nother) battery charger that was able to force a small charge into the battery then started a normal charge cycle. There doesn't seem to be any ill effects.
 
What lighycycle said, any decent lithium battery should have a BMS that prevents them from being drawn below their critical voltages. Because once a lithium battery has been drawn down below those critical voltages, they are irreparably damaged.

So, assuming the BMS cut off the output before it got to that critical voltage, what you are seeing on your voltmeter may just be a little bit leaking past the BMS or something. I would try to get some charge back into it and see if it wakes up.

A smart charger will often refuse to even try to charge a battery with the voltage that low, and even many battery tenders now will not activate and try to charge when they detect the voltage that low as there is a risk of a reversed cell in a lead acid application, so you may have to hunt for an old school dumb charger, or hook up a set of booster cables between your car and the bike for 10-15 minites and see what happens.
 
Howdy all. Thanks for the replies. The battery isn't salvageable as far as I can tell. I've only tried with one lithium charger, I'll try with a second one when I get it back and see, but I think it's a goner.

Lightcycle said:
What kind of battery is it? Brand and model?

Most Lithiums have algos in their Battery Management System (BMS) which will prevent damage from deep discharges, always keeping a minimum reserve charge inside regardless of what is drawing from it. So it *may* be recoverable without negatively affecting future battery life and performance.

Recharge and keep your fingers crossed!

Maybe install a dedicated USB socket on a switched power relay to prevent accidental discharges through parasitic draws? All it takes is one time to forget to hit the off button on that USB socket...
Click to expand...

I didn't want to name-and-shame until I knew who to point the finger at (myself, or the manufacturer), but since you asked, it's an EarthX ETH18B.

Tapping into a switched power source was kind of a future plan specifically to avoid this type of situation. On newer versions of my bike there's already an accessory port like that. On my 13 year old girl, nope, it's always on. Wah :(

I was posting, less to find solutions, and more to satisfy my curiosity on if this battery failure was my fault, or the manufacturer's. Any thoughts on where should I point the finger?
 
Try putting a charger on it then hitting it with booster cables to reconnect the BMS

Sent from my Pixel 5 using Tapatalk
 
xrljoel said:
I completely drained a new LI battery on my Husqvarna 250 by leaving the key on.

I bought a(nother) battery charger that was able to force a small charge into the battery then started a normal charge cycle. There doesn't seem to be any ill effects.
Click to expand...

Interesting. Which charger worked for you?
I have the OptiMATE Lithium 4s 0.8A, TM-471, and it doesn't seem to be able to do the job.

I once 'revived' a dewalt battery that wouldn't take a charge by wiring a good dewalt battery to the bad one for a second or two. Some sparks flew, but that was enough to get just the wee bit of juice into the dead dewalt battery for it to be able to take a charge again.

Should I try something this, outdoors, the next time it snows? haha
 
adri said:
I didn't want to name-and-shame until I knew who to point the finger at (myself, or the manufacturer), but since you asked, it's an EarthX ETH18B.
Click to expand...

You're in luck. From: Frequently Asked Questions About EarthX Lithium Batteries

The ETX-Series of batteries have over discharge protection and is designed to prevent a continuous active drain on the battery to the point of damaging the battery, such as leaving your key in the on position, master switch on your aircraft, or parasitic draw as examples. If your battery is reading 0V, or near 0V, then this protection might be activated.
Click to expand...

adri said:
Howdy all. Thanks for the replies. The battery isn't salvageable as far as I can tell. I've only tried with one lithium charger, I'll try with a second one when I get it back and see, but I think it's a goner.
Click to expand...

As PP and XRL mentioned above, try using a dumb trickle charger, not a float or smart charger. The latter have algos in the circuitry which prevent a charge going in if it detects a super-low voltage. A trickle charger will just force the voltage in regardless of what the battery is reading.
 
Lightcycle said:
As PP and XRL mentioned above, try using a dumb trickle charger, not a float or smart charger. The latter have algos in the circuitry which prevent a charge going in if it detects a super-low voltage. A trickle charger will just force the voltage in regardless of what the battery is reading.
Click to expand...

This! A dumb charger or booster cables are needed!
 
adri said:
I have the OptiMATE Lithium 4s 0.8A, TM-471, and it doesn't seem to be able to do the job.
Click to expand...

Yep, don't use that one. It will only charge if it senses a minimum voltage.

I was going to link to a cheap dumb trickle charger on Canadian Tire, but holy heck, they're all smart chargers now!

Here's an old one I'm talking about:

www.policeauctionscanada.com

MotoMaster 11-1543-6 12V Trickle Battery Charger (270734A)

MotoMaster 11-1543-6 12V Trickle Battery ChargerSKU#270734AKeep your various vehicle and equipment batteries charged with this small and convenient battery charger from MotoMaster!Features: - Brand: MotoMaster- Model: 11-1543-6- For lead-acid batteries- Power: 12V 1A- 12' output cables with 50...
www.policeauctionscanada.com www.policeauctionscanada.com

e13ef56d-095e-4357-8d3f-001845e27d71_fullsize.jpg

I think I have this exact one, they were $9.99 at CT.

Back in the day... :oops:
 
A bench power supply can work too. Added bonus for showing you voltage and current. Jumper cables can work in a pinch but may have way more amps than you'd like.

I keep a dumb charger around for times the smart ones are too smart for their own good. Most of the smart ones have lots of useless modes, why can't they include a dumb 2A mode? That one would be really useful.
 
adri said:
Interesting. Which charger worked for you?
I have the OptiMATE Lithium 4s 0.8A, TM-471, and it doesn't seem to be able to do the job.

I once 'revived' a dewalt battery that wouldn't take a charge by wiring a good dewalt battery to the bad one for a second or two. Some sparks flew, but that was enough to get just the wee bit of juice into the dead dewalt battery for it to be able to take a charge again.

Should I try something this, outdoors, the next time it snows? haha
Click to expand...
It was this one:

General PDP Template

www.canadiantire.ca www.canadiantire.ca

Used the Force mode.
 
GreyGhost said:
I keep a dumb charger around for times the smart ones are too smart for their own good. Most of the smart ones have lots of useless modes, why can't they include a dumb 2A mode? That one would be really useful.
Click to expand...

Was trying to find a cheap dumb charger for @adri, but I'm hard-pressed to find any online. They're all smart chargers now. Even on the Walmart site, they're all "smart".

Will our vintage dumb chargers be super-valuable now? Keeping mine forever.
 
GreyGhost said:
smart ones are too smart for their own good. Most of the smart ones have lots of useless modes, why can't they include a dumb 2A mode? That one would be really useful.
Click to expand...

My current smart charger has 2 alternate modes, “Maintain” (which is basically battery tender mode) which still won’t try to put out any voltage to a really dead battery, and “Reinforced activation” or something like that which *will* stuff out voltage regardless of the starting voltage it sees.

I accidentally killed the battery in my Volt overnight a few days ago and when I hooked up my smart charger it said 6v. Regular mode did nothing even at the 40a setting. The reinforced mode started bringing it back up slowly to a point where I was able to get the computers in the car to wake up, and then get it turned on at which point the DC-to-DC system took over and pounded 140a at the dead battery lol.
 
PrivatePilot said:
My current smart charger has 2 alternate modes, “Maintain” (which is basically battery tender mode) which still won’t try to put out any voltage to a really dead battery, and “Reinforced activation” or something like that which *will* stuff out voltage regardless of the starting voltage it sees.

I accidentally killed the battery in my Volt overnight a few days ago and when I hooked up my smart charger it said 6v. Regular mode did nothing even at the 40a setting. The reinforced mode started bringing it back up slowly to a point where I was able to get the computers in the car to wake up, and then get it turned on at which point the DC-to-DC system took over and pounded 140a at the dead battery lol.
Click to expand...
How did the charger feel about another charger coming on line in parallel? I assume it just thought the battery was charged and gave up?

How did you kill the 12V battery? I thought the volt automatically kept it topped up? I guess if the HV battery was dead that wouldn't work.
 
Lightcycle said:
Next topic: Desulfation Mode

Snake oil or Real deal?

I have my doubts. Maybe the batteries I've used this on are really old, but I've never recovered a deeply discharged battery with desulfation mode to a point where it lasts any useable length of time after.
Click to expand...
I have had no luck with Noco repair strategies. On the other hand, my dodgy chinese battery thing (KONNWEI KW510) has worked magic on some batteries. Starting from about 30% of CCA and recovers them to about 80% which is good enough for many applications. It can't save them all but it has saved me more in batteries than I paid for it.
 
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