Received my Audew 2000 approx. 7 days ago, came @ 74%, charged it until 100%, in my POV for the last 7 unused & checked just now still showing @ 100%.
Received my Audew 2000 approx. 7 days ago, came @ 74%, charged it until 100%, in my POV for the last 7 unused & checked just now still showing @ 100%.
So, you got the good one!Originally Posted by OldRunner/CSAT Neighbor
There's nothing civil about this war.
Some quick stuff:
1) Lithium ion cells of most chemistries have a very low self-discharge rate.
2) Lithium ion batteries have some sort of a battery management system to prevent them from being unsafe through abuse (charged at too high a rate, charged below freezing, or charged after discharging to 0V).
3) The battery management system does require power all the time. A well-designed BMS has a very low quiescent current, and shouldn't drain noticeable amounts of charge in days.
4) The state of charge and state of health values reported by the BMS are an interpretation of voltage measurements through an algorithm. There are good ones and bad ones, and there are various states of the battery that can throw off SoX (not to get into it, but usually in the transition between when the battery is under load and when it's not; it can take time).
5) A lithium ion cell with a defect can drain quickly. In that case I would expect it to be a recurring phenomenon. I also wouldn't store such a battery near a basket of oily rags.
6) A defect in the BMS can drain the battery quickly. Again, I'd expect that behavior to repeat.
7) Lithium ion cells do break in, but that's typically accomplished during the manufacturing process. The effect is that capacity increases. I don't think that would explain the behavior you saw.
8) They aren't sitting at 100% SoC even if that's what the meter reads. The best way to tell is to measure the voltage across the terminals. The jumper batteries that you and I have are a big pile of cylindrical cells in parallel, so we (nor the BMS) can't tell what's going on with each individual cell, so there's some masking we'd have to math our way through.
So for Blues, I'd say there was something interesting about the SoC measurement approach that didn't like where it was, and it's now over it. I would not expect the battery to be unreliable, and if it doesn't do it again I'd ignore it.
In general, it's a good idea to find an occasional use for your jumper batteries, so that you remember to charge them every three months or so.
Thanks, @JAD, for that succinct explanation.
There's nothing civil about this war.
@JAD, do you recommend the same for rechargeable lithium cells, (16650, 18650 etc), in our flashlights when dormant for months?
I've noticed that all of mine hold the bulk of their charge...only dropping from 4.2v to about 4.17 even over extensive periods.
Thanks.
There's nothing civil about this war.
Single cells and pairs have relatively simple protection circuits which are outside of my basket (the last system we commissioned had 12,480 cells each 64 Ah). However I’d expect them to use very little or no juice, and very little balancing activity — so they should do what you’ve observed. Jumper batteries are lots of cells in parallel so lots of balancing and hopefully a more complex protection approach.
As mentioned above, I had sent an email to Audew via their website asking whether the drop in charge after six days of being idle was normal for their device...the following is their (somewhat comical) reply:
So, I think it's safe to say that I'll be making a decision on whether to return the unit to amazon before January 31.We received your letter.
We are sorry for causing problems for you.
Could you give us a detailed explanation?
We still wanna fix this issue for you and hope you understand and give us a chance. We really appreciate you could provide us with the video/photos because we are unable to confirm the issue and process the request without video/photos. In order to solve your issue faster, could you please take help from someone?
These are the ways to send videos/photos, thank you very much for your cooperation!
About the video: Please upload the video to YouTube, then send the link to us as text or a screenshot. Please do not send a hyperlink, otherwise the link will be removed by Amazon.
About the photo:
Please send us an image of the attachment format via the "Seller Message" on the Amazon platform.
Please do not worry, after confirming the problem, we are willing to give you a reissue or a refund.
Waiting for your letter.
Best regards(But hopefully JAD's prediction is correct.)
There's nothing civil about this war.
I ended up buying a NOCO GB40 when this thread started. So far it’s jumped my Jeep at least once and my work Tahoe twice. It’s a lot easier than using jumper cables.
Just a dog chauffeur that used to hold the dumb end of the leash.
My Audew 2000 came today.
It was 71% out of the box.
Charged to 100% in 2 hours.
I hooked up an iPhone 7 and an iPhone 11 that were at around 30% charged and charged them to 100%.
The Audew showed 62%. Charged it back to 100% and will check the charge in a few days.
Update:
The pattern holds. Six or seven days from charging the unit from 80% back to 100% and checking it once each morning, it's back at 94%.
This does not inspire confidence (in me) and I will most likely return for refund as opposed to an exchange.
I may hold on to it for a while before returning to see how it progresses from here, (since I have the ability to return by end of January, 2021), but not sure I will.
There's nothing civil about this war.
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