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2018 136 HR Ont.
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I just took some updated pics.
It looks like you have a washer between the two lugs on the mega fuse. That shouldn't be there, there seems to be an extra washer on the other side of that fuse as well. Lug to fuse, contact to contact no extra washers between current carrying components, ever.
I would be interesting if you were to measure your voltage drops across your connections before and after removing the improperly placed washers.
 

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Also i would check the voltage on those circuit breakers once you get your multimeter. Read a few post people have issue with those cheaper breaker. You can also bypass the all the circuit breaker and see if it will solve the issue.
 

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Discussion Starter · #24 ·
Thanks again for the responses. Sorry to trouble everyone with it! I planned on troubleshooting on my own with some already made guides. This is better obviously so I appreciate everyone helping.
 

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Discussion Starter · #25 ·
Slept in the van last night everything was great. Cooked on induction cooktop watched movies not using the inverter. Got up this morning, turned on the inverter with the Chinese diesel heater running and poof it all bricked out. No power again. I checked the voltage and it was saying .6v. I had over 80 percent battery left and no issues at all until I switched that inverter on. Bad batteries? I'm confused!
 

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Slept in the van last night everything was great. Cooked on induction cooktop watched movies not using the inverter. Got up this morning, turned on the inverter with the Chinese diesel heater running and poof it all bricked out. No power again. I checked the voltage and it was saying .6v. I had over 80 percent battery left and no issues at all until I switched that inverter on. Bad batteries? I'm confused!
What was voltage before? A voltage of .6v means that your BMS has kicked in and shut the batteries down to protect them.

A battery shunt only works if it has been properly calibrated. That means it needs to know when your batteries are full, and how many AH you have. If you told it your batteries were full when in reality they were only 40% all your readings will be off.

Also - what is this mythical induction cooktop that can be used without using the inverter?!
 

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I used the inverter last night to use the cooktop! Sorry I wasn't clear lol. I looked up the battery reviews and got this wonderful info. Yuck this is what I get for not buying Battleborn I guess lol
Plenty of good non-battleborn batteries out there, (SOK, Renogy) but this doesn't seem to be one.

Just to make sure, charge the battery up to 14.4v and see if things still don't work. Might want to contact their warranty department too. No sense in completely giving up.
 

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Discussion Starter · #29 ·
Plenty of good non-battleborn batteries out there, (SOK, Renogy) but this doesn't seem to be one.



Just to make sure, charge the battery up to 14.4v and see if things still don't work. Might want to contact their warranty department too. No sense in completely giving up.
I/QUOTE]

I agree. I already have contacted them. Hopefully they will do something to fix it but yes I agree stay away from them sadly. I was looking at the sok line up and almost just pulled the trigger on them but figured I should wait to see if this company can fix the problem.
 

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I am not saying if those batteries are good or bad, but before you purchase anything else, consider carefully why it isn't working out and what needs to change in order to be successful.

Li based battery technology CAN charge and discharge very fast, but the problem is that it will do this so fast that it will destroy itself in the process unless managed. There are two parts to managing a Li battery
  • the user and
  • the built-in BMS protection equipment.

1) Inverter start up example:
In order to be stable, inverters and chargers have a fairly large capacitor on the DC input. These capacitors have essentially infinite ability to absorb current until they are filled up.

When the battery is connected to this (turn on breaker) , a fairly massive current flow will flow from the battery to these capacitors on a cold start up. Far higher than any practical van battery pack can sustain without tripping the internal BMS of a Li battery. With an AGM battery, the battery will self limit, but with Li, the effect is to trip the BMS. This is completely normal and happens all of the time with pretty much every LiFe battery on the market.

There are three common ways to deal with this:
  • Use a charger or other battery to first bring up the voltage of the power system to normal operating range and charge up those capacitors
  • Create a "pre-charge" path from the battery to the system using a separate small circuit breaker and in line resistor. This has been a common approach for a long time, but the typical consumer won't implement the needed components so it has fallen into disfavor.
  • "Pump up" the capacitors in steps. Basically you turn on the breaker, let the BMS trip, turn it off for 20 - 30 seconds so it re-sets, turn it on again. Repeat until it works.

Again - these steps are normal parts of a Li based, power system "start up".

In the original design of the BB batteries - and many others, the built in BMS could actually blow out during start ups. Now most are fairly resistant to this. In the case of BB, the BMS auto re-sets after 20 - 30 seconds - don't remember the exact number. Some batteries use a BMS that is re-set by charging.
 

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2) Current output limits

There is a lot of marketing done by Li battery companies because it is so competitive about how much current can flow before it starts to be faster than the BMS or internal cell design can handle.

The reality is that there are only a handful of commercial BMS circuits used by LiFe battery companies and most of them will only run reliably at 50 - 75 amps continuous. A few high end ones will run more, but still very few can really sustain 100 amps continuous before they get too hot and trip.

The battery that you have purchased is being sold as a "deep discharge" battery, and the example of how it is being used on the amazon photo is of a low current / deep discharge usage.

No matter which LiFe battery that you purchase as a typical consumer, you need to accept that each one can only supply ~ 50 amps / 600 watts per battery to the load.

In your use case of a 2000 watt inverter,

(2000 watts) / 600 watts per battery = 4 batteries

This is how many batteries you need to run your electrical setup.

That is why in all van electrical builds that I do, a 2000 watt inverter is paired with 4 batteries. That is what it takes to be reliable and stable.

Having high capacity batteries - for the most part - doesn't change this basic number.

Really the same is true for most batteries, regardless of chemistry. 50 amps per battery load is a good target design for a van power system.

____

Your batteries may or may not be working as well as can be expected - I don't know.

Try to use them with a smaller inverter load - like a power drill and see if that trips them.
 

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2019 Promaster 3500 Silver high top 159"
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2) Current output limits

There is a lot of marketing done by Li battery companies because it is so competitive about how much current can flow before it starts to be faster than the BMS or internal cell design can handle.

The reality is that there are only a handful of commercial BMS circuits used by LiFe battery companies and most of them will only run reliably at 50 - 75 amps continuous. A few high end ones will run more, but still very few can really sustain 100 amps continuous before they get to hot and trip.
...
Just a data point:

I use the recommended 2x Renogy 100ah smart lithium with their 2kw inverter/charger and I have tested 190a draw for ten minutes without issue (after removing all cheap thermal breakers).

Renogy specifies 3x for the 3kw unit. It would appear that their specified continuous rating of 100a is good. I have tested a single battery at 110 amps (while diagnosing the aforementioned POS circuit breakers) and they didn't shut down, but did throw a warning on the battery display. They are specified to shut down at 130a.
 

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Discussion Starter · #34 ·
Your batteries may or may not be working as well as can be expected - I don't know.

Try to use them with a smaller inverter load - like a power drill and see if that trips them.
Holy wow information. Thank you so much. The problem with that is it trips.....without anything being on. It's tripping the whole system as I turn the inverter on. Forgive me if I'm wrong .... But I'm gathering that I would have been better buying 4 100 ah batteries instead of 2 200ah batteries? Sorry if I am misunderstanding. Just riding home from Thanksgiving feasts!
 

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What is the specified Max BMS current for your batteries? Even a low .5c (100a) x 2 should easily support the inverter.

Oh, here it is:
From EP12200 (media-amazon.com)
Product Font Rectangle Screenshot Parallel


150A is "low rate" for a 200AH battery. Two in parallel should be plenty to run your inverter. Something else is wrong. There is NO WAY the inverter is drawing > 400A for three seconds unless something is seriously wrong with the inverter. Possibly issues with the battery. Maybe disconnect one and try again with an <1kw load. A single battery should drive that fine. Possibly one battery is not performing properly?
 

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Discussion Starter · #39 ·
What is the specified Max BMS current for your batteries? Even a low .5c (100a) x 2 should easily support the inverter.

Oh, here it is:
From EP12200 (media-amazon.com)
View attachment 80189

150A is "low rate" for a 200AH battery. Two in parallel should be plenty to run your inverter. Something else is wrong. There is NO WAY the inverter is drawing > 400A for three seconds unless something is seriously wrong with the inverter. Possibly issues with the battery. Maybe disconnect one and try again with an <1kw load. A single battery should drive that fine. Possibly one battery is not performing properly?
Great! I will try that tomorrow. Thanks, I'll let you know. :)
 
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