Battery voltage is too low and I have no way to charge

chrisski said:

I do agree with that, but how about charging to 3.6 per cell (14.4 volts) on new to him lithiums that are not grade A because they were delivered at 3.29 per cell but have since dropped to 3.0 per cell with no BMS? I would not do that with mine.

I’m only on my third lithium build, the first two were basically toysgetting me ready for the third I’m building, so I could very well be wrong.

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I think my other post said what can be done till he got a bms, 14.4 was not in my reply.

October 30, 2019 till January 29, 2020 I ran my batteries without a "bms" just lowered my bulk/ absorb to 13.9v till I replaced the bad senseboard on the cell. I'm not using cheap cells though and after 2.5 years I knew my system/ batteries.
Edit: I should note that 14.1v is my absorb voltage and for 10 minutes max it can't be turned off.

ruiz.manuel94 said:

Do you guys think It is okay If I charge using solar WITHOUT BMS?, just to check everything is working fine. I would monitor voltage just to charge up to like 50%

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NO!

Yesterday you came in here all like this:

ruiz.manuel94 said:

I am a newbie and I am very worried to have damaged my new cells.

I have the following questions:
-Have I damaged my cells permanently?
-Should I charge my battery as soon as possible to avoid further damage? (charging options are limited, see next question)
-Is it safe to charge using any of these: 50 A car battery charger (came with my ambulance PM) or this other battery charger?
-Should I wait till I get my BMS and panels to recharge? (1 week without further discharging, obviously)


Please help me I am very worried.

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and now that it turned out that your fine, you want to keep taking risks. STOP! Slow the hell down get all your gear in place and do the job right.

I am honestly completely sick of the whole top balancing topic. After having done the whole parallel top balancing thing I have come to the conclusion it is a stupid waste of time and mental energy unless you dont have the money to buy this. If you dont then yes, you must parallel top balance but if you can afford the $100 dont waste the time. Install the balancer, charge the pack until the BMS stops charging, stick a bench top power supply on set to 3.65v X the number of cells in series you are charging and walk away. I have done this a couple times now and it is so easy and fool proof. No taking the battery apart and putting it back together and because it is balancing at 4 amps it is super fast.

noenegdod said:

and now that it turned out that your fine, you want to keep taking risks. STOP! Slow the hell down

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LOL! damn dude chill! But you are right, I tend to do that haha.

So you know what you are right, I'm just gonna enjoy Christmas, stuff my face with food and forget about my battery.

And when I get the BMS I can get to work and finish the job right!

Thanks for your help

PS: do you think I can charge the pack using my alternator in the meantime? (just kidding)

ruiz.manuel94 said:

LOL! damn dude chill! But you are right, I tend to do that haha.

So you know what you are right, I'm just gonna enjoy Christmas, stuff my face with food and forget about my battery.

And when I get the BMS I can get to work and finish the job right!

Thanks for your help

PS: do you think I can charge the pack using my alternator in the meantime? (just kidding)

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LOL. We all do.

The post was actually intended to be funny but a someone reported it and moderator took the original down because I made a little off color joke about being a young pubescent 14 yr old and going too fast in it. Ill pm you the original so you can have a laugh at it in private.

All right people! the wait is over, my panels and BMS are in!!!!

I have been reading on the top balancing subject, as far as I understand, the only benefit is that it will maximize the usable capacity of the pack.

The thing is I have three days only before my first trip (2 week trip) on the van, and I have no time to balance properly.

From what I understand, it is ok to run a few cycles without top balancing, given that the cells are not radically unbalanced (they are 2.98 - 3.01 now and were all 3.23 when delivered)

Am I in the correct understanding? Or am I acting like a 14 year old with a hard on again?

As long as you connect the BMS properly, the cells will be protected.
You may lose some overall capacity, and the charging may stop too soon, but the battery will work for your trip.

ruiz.manuel94 said:

All right people! the wait is over, my panels and BMS are in!!!!

I have been reading on the top balancing subject, as far as I understand, the only benefit is that it will maximize the usable capacity of the pack.

The thing is I have three days only before my first trip (2 week trip) on the van, and I have no time to balance properly.

From what I understand, it is ok to run a few cycles without top balancing, given that the cells are not radically unbalanced (they are 2.98 - 3.01 now and were all 3.23 when delivered)

Am I in the correct understanding? Or am I acting like a 14 year old with a hard on again?

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LOL, nope, your good. As long as you have the BMS connected properly like Supervstech said.

Supervstech said:

As long as you connect the BMS properly, the cells will be protected.
You may lose some overall capacity, and the charging may stop too soon, but the battery will work for your trip.

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Sweet, I got it all wired up already, just need to mount the panels and charge then!!

After the trip I am looking to go for your method (using laptop supply):

Supervstech said:

I use this. I hook it to a stable battery, or laptop power supply, and set the desired parameters. Works great.

https://www.amazon.com/UCTRONICS-Ad...&sprefix=buck+boost+controller,aps,60&sr=8-20

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I like this because it is cheap and I have two old laptop power supplies around. (not looking to spend much on a charger I will use once)

Could the laptop power supply setup be used to charge like a "shore power" charger when needed? I assume one would have to monitor and adjust the charging voltage manually as the battery charges. But I would use this only for extreme cases.

Thanks for your reply

There are some good capacitor based active balancers available! Get one. You'll be happy with it and can even disable the resistive balancing features of the daly.

That is what I have done with my 42 kWh pack. I have an expensive Orion BMS which I use for monitoring and control. I has great reporting but low balancing currents so I disabled the balancing and use a Heltec 2 Amp active balancer.

ruiz.manuel94 said:

I have been reading on the top balancing subject, as far as I understand, the only benefit is that it will maximize the usable capacity of the pack.


From what I understand, it is ok to run a few cycles without top balancing, given that the cells are not radically unbalanced (they are 2.98 - 3.01 now and were all 3.23 when delivered)

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They look balanced now at this voltage/state of charge. They could be divergent, you won't know until you try.

As you charge with BMS, one cell will approach maximum voltage before the others, and probably cause BMS to disconnect. Will yours disconnect for current flowing to charge only, but still allow discharge?

If possible, reduce SCC voltage setpoint so highest cell hovers below over-voltage disconnect setpoint. That should allow BMS to resistively bleed off current and keep it at that voltage, while same current gradually charges the other cells.

Even if that takes forever to bring cells into balance, having SCC terminate charge without BMS disconnect should be better. That's how you will want it to work even when balanced, just a higher voltage setpoint when all cells are part way up the knee together.

ruiz.manuel94 said:

All right people! the wait is over, my panels and BMS are in!!!!

I have been reading on the top balancing subject, as far as I understand, the only benefit is that it will maximize the usable capacity of the pack.

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Nope. Additionally, cell runners may prevent you from reaching your desired absorption voltage. It can be frustrating having the BMS cut out prematurely. You may find that you have to lower the absorption voltage enough that charging takes longer than you'd like.

ruiz.manuel94 said:

The thing is I have three days only before my first trip (2 week trip) on the van, and I have no time to balance properly.

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You actually do. Balancing is mostly a hands-free effort.

ruiz.manuel94 said:

From what I understand, it is ok to run a few cycles without top balancing, given that the cells are not radically unbalanced (they are 2.98 - 3.01 now and were all 3.23 when delivered)

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Those voltage levels say absolutely nothing about balance or unbalanced. Cells with substantial deviations in SoC will show negligible resting votlage differences. I've seen deviations as large as 40% in the mid-range with no noteworthy deviations in voltage.

ruiz.manuel94 said:

Am I in the correct understanding? Or am I acting like a 14 year old with a hard on again?

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Almost. Maybe.

ruiz.manuel94 said:

Sweet, I got it all wired up already, just need to mount the panels and charge then!!

After the trip I am looking to go for your method (using laptop supply):



I like this because it is cheap and I have two old laptop power supplies around. (not looking to spend much on a charger I will use once)

Could the laptop power supply setup be used to charge like a "shore power" charger when needed? I assume one would have to monitor and adjust the charging voltage manually as the battery charges. But I would use this only for extreme cases.

Thanks for your reply

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Mine can be set from .6V to 36V and 5A so, to use it as a shore power charger, you would have to set it to bulk v, then manually set it to absorb, but it works great, and has cool features, Wh tracking, charting, etc.
I don’t use it above 3A, so it doesn’t get hot.