LiFePO4 Install

[john61ct]

Good news that the cells themselves are OK.

They may elect to replace the BMS and ship it back, you do not want to mess with replacing components yourself if it's supposed to still be under warranty.

This incident really illustrates the benefit of a design where

cell voltages are accessible, ideally balance leads physically available, and where

the BMS can be bypassed / upgraded etc by the user.

The concept of a "drop-in for dummies" where the design protects **against** the user, IMO just say no.

 

[Alloy]

Some people and vendors have no problem with holding all the way to Zero amps acceptance.

Personally I think that's too stressful for good longevity, especially at 14.6 but IMO even at 13.8 (3.45Vpc)

and most especially at low charge currents available.

The 0.01C endAmps point is a good "highest SoC" stopping point for "vendor Full" benchmarking, and 0.03C for daily usage cycling, resetting the SoC meter frequently etc.

But other than those reasons, the battery health ideal is staying at **lower** SoC, as in 30-50%

Certainly for storage, no cycling for days

But even if you just aren't drawing much at the time.

Sitting anywhere near Full for long percentages of the bank lifetime, shortens it significantly.

Opposite of caring for lead, so hard to break that mindset.

The BMS-balancing requiring sitting at Full for long periods of time is IMO stupid, but very common and in this case nothing to be done.

When I was looking into Lithium the pre-assembled banks had the BMS set at less than 100% SOC but it was only 90-95%. Ended up adding 20% more to Lithium $$ when comparing to FLA.

 

[Alloy]

Good news that the cells themselves are OK.

They may elect to replace the BMS and ship it back, you do not want to mess with replacing components yourself if it's supposed to still be under warranty.

This incident really illustrates the benefit of a design where

cell voltages are accessible, ideally balance leads physically available, and where

the BMS can be bypassed / upgraded etc by the user.

The concept of a "drop-in for dummies" where the design protects **against** the user, IMO just say no.

Gel/AGM/Carbon have similar issues.

Being able to test (voltmeter or a hydrometer) individual cells makes troublshooting easier.

 

[Rando]

I am almost certain the BB bms uses a single solid state relay. Slow charge current indicates excessive voltage drop across the relay. During discharge that would rapidly overheat the relay, causing drop out.

If BB denies a warranty claim, you could always crack open the case, and replace the faulty relay. I am certain you could find a off the shelf replacement that would work.

According to BB, they have separate channels for charge/discharge which would indicate at least two MOSFET banks or two SSRs with an 'ideal diode' controller. I would guess they are using MOSFETs and there is nothing wrong with that (that is what is inside a DC SSR anyway). Hopefully they are not using actual diodes, or the body diode on the MOSFETs to control current direction as that would lead to 0.3 - 0.7V drop and a bunch of heat at high currents.

Anyway, warranty this thing, stat. That is why you paid the premium to BB to buy it in the first place.

 

[luthj]

Good information. Do you have any links to BB technical documentation?

It sounds like they are using a bi-directional relay, but it may be a single unit, or a bank of components. My discreet IC knowledge is somewhat limited, so I would deffer to your experience.

 

[Rando]

It is pretty clear that BB is going after the consumer market and not the professional market. Their 'specification documents' is a marketing flier largely devoid of actual specifications or performance metrics, and instead have vacuous claims like: 'Where are your batteries made? All of our batteries are designed and assembled in Reno, NV, USA.' (which appears to be stretching the truth a little).

If you read between the lines in their manual it appears that they have individual control of charge/discharge.

It would be great to see a teardown of one of these batteries at some point and see what is actually inside. Hopefully the prices on LiFePO4 batteries from established manufacturers will come down sometime soon.

 

[dreadlocks]

well apparently the BMS went into protect mode charging it back up, BB is sitting at 0.00V again and the BMV's showing its still 25AH shy of being full.

BB Support been responsive this morning, been probably overwhelming em w/data.. hopefully I'll get my RMA# shortly.. Ive not mentioned this thread or anything, dont want special handling because the public is watching em.

 

[john61ct]

When I was looking into Lithium the pre-assembled banks had the BMS set at less than 100% SOC but it was only 90-95%. Ended up adding 20% more to Lithium $$ when comparing to FLA.

FLA usable Ah is usually rated at 50%, LFP you can set the hi/lo wherever you like, avoid the "pre-assembled" if you can't.

No reason not to use 85% of capacity when needed, but best to not go that low regularly if you want them to last decades.

 

[john61ct]

Hopefully the prices on LiFePO4 batteries from established manufacturers will come down sometime soon.

Ain't gonna happen for the top quality bare cells anyway.

The BMS market is really due for a huge disruption, FOSS projects should be developing much faster.

So much profit in packaged systems, room for real competition there, but it takes so many years before a good reputation becomes credible. . .

 

[MapJunkie]

The BattleBorn is dead, cant find my multimeter right now.. but I pulled the battery and it wont even fire up a test lamp that I have confirmed working.. not sure ****** happened here.

Guess we're gonna find out how good this 10yr warranty is on BattleBorn, stay tuned..


Here is a breakdown so far as I can recall:

• Labor Day weekend.. Friday night everything was normal.. Woke up Saturday to 50% SOC
• Made Coffee just fine saturday morning, deployed portable solar in evening when apparent fixed was not gonna cut it.. Got back up to 85% SOC.
• Sunday Morning woke up, battery @ 40% SOC..
• Tried to Make Coffee, but coffee machine clicked off moments after turning on.. Didnt have tools to dig into it so fired up Genset and made coffee.
• Sunday night battery was back up to ~85% SOC
• Monday Morning, about 35% SOC.. tried again to Make Coffee.. still failed same way, used genset again..
• Packing up camp all power cut off when everything looked fine, crawled into space and started checking fuses and stuff and it came back on all on its own without messing with anything.
• Drove home Monday 11am to 5pm, expected full charge when I got home due to Solar.. but was still sitting at ~40% SOC when I got home, assume the LVD dropped the battery or something.
• Plugged it into shore power in driveway, charged it up to ~80% SOC until BMV Alarm for high temp (110F) was hit.. disconnected battery went to sleep. had been a hot day I figured.
• Tuesday Morning charged it to 14.6v, Recalibrated SOC, made some tweaks to BMV settings, and pulled charger immediately once it stopped taking a charge, kept an eye on temps and they were just above ambient.. let it sit idle the rest of the day.. was resting at about 13.8v
• Wednesday went out to check inverter, again same failure mode.. crawled into crawl space to check error fault on Inverter.. low voltage, check cabling.
• Monitored voltage and it was going all over the place, seemed dependent on load.. (see attached screenshot)
• Disconnected Inverter, Solar, and AC Charger, bypassed Battery Protect
• Put a wrench on the Shunt and found I could tighten the output of the shunt up a little bit, but was by no means loose.. went and checked the voltage.. still seemed low but was staying above 12v, thought I had found the culprit.. in retrospect i shoulda watched it longer.
• Pulled Disconnect, Installed new ground bus bar, hooked everything up to new bus bar.. went back into the trailer expecting everything to be fine when I reconnected.
• Nothing worked, BMV dead, Disconnected everything again, only BMV hooked up to battery.. still no power..
• Removed Battery, put it on a test lamp.. nothing, not even a flicker of light.

I don’t know if BattleBorn is like Valance liFePO4, but I was able to wake up my very dead battery with some babying. I used a charger (Victron IP65) that had a battery recovery mode. Tue battery needed 1A to get back to 12v. When do charges with a regular charger, it wouldn’t charge.


Sent from my iPhone using Tapatalk

 

[dreadlocks]

update: I was told to fill out RMA form and the'd send me a shipping label (which I didn't expect).. dunno if they are mailing me return packaging or if I'll just get an email this week w/a label.

planning a 10 day vacation in mid october, hopefully this is resolved by then.

 

[luthj]

I hope their warranty checks are quick. I suspect it will take several weeks for them to issue a refund, as someone needs to physically test the battery. If their QA/factory facility is where the battery is going, they will have a test stand, so it may be pretty quick.

 

[john61ct]

Refund?

Not limited to just a replacement?

 

[dreadlocks]

I'm expecting a refurb and the same unit returned.. would be surprised w/a refund after a year of usage.

 

[john61ct]

very

But a reco exchange might be better than waiting for them to repair your specific unit.

Likely choice is up to them, read the fine print.