So learning, and learning, and learning. I apologize I am not a smart man and I can't find an answer on google.

I am putting together a LIfepo4 36V system for my boat trolling motor. Confirmed trolling motor batteries, ordering new onboard charger specific to LiPo4, and now looking at battery monitors. I see a ton of them that are cheap but dont seem to come with a shunt. Can I just install the meter? Do I really need a shunt? BTW not SUPER SUPER concerned but would like a general idea of charge/volts. I am super easy on stuff (my lead acids from walmart usually last me 6 years of continuous use in my boat, and my batteries in my car have lasted 10+ years, I like to do preventative maintenance LOL).

I am having trouble with my 12v lithium battery (120Ah LiFePO4), in that it will not accept charge from any source.

It is at a low state of charge and rests at 12.4v. When connected to any charger (have tried multiple) the voltage climbs briefly (~14.4v) and within a few seconds it drops back down to 12.4v and the charger status resets.

I could be wrong but my theory is the cells are out of balance and the BMS is cutting out due to over voltage on one of the cells.

Also applying a small load (7amp) pulls the voltage down to about 9.5v, which I'm assuming is due to low capacity in one or more of the cells.

If this is the case, is there a way I can rebalance the cells without pulling the battery apart? (ie while they are in series) Would completely flattening it to 10v then recharging help? It may have a passive balancer built in but I'm not sure.

It's only 6 months old so the next step would be going back to the manufacturer

Any suggestions are appreciated!

I have been looking to plug my Pi Zero based pi-hole into a UPS. So instead of buying a commercial device, I though of utilizing the various spare i have lying around. I may need the UPS only fro few minutes when I am switching off the power supply or moving the pi zero to my desk for any experimentation.

Circuit Inspired by this post

PFA the parts:

1. 9 V ac to dc adapter

2. a Constant Voltage Current Limited power supply board

3. Diode to act a switchover

Normal voltage on the power line is 9V which supplies the buck converter. 9v on the line does not allow the NiMh cells to power the buck converter due to the diode.

When power fails, the the NiMh cells take over and supply the buck converter through the diode.

4. DC-Dc buck converter

5. 6 NiMh rechargeable batteries

Diagram below, thoguths / comments?

https://preview.redd.it/o6be0f0rviwc1.jpg?width=922&format=pjpg&auto=webp&s=085ab6f1359eced88a03a6f3c994b4760e33c09c

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TIA

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Hello, recently built a camper and needing some help figuring out the maxx air fan I installed. The fan says it will run 12v-24v. I have a 18v rigid drill battery inverter. I have it connected through the 24v plug and it works just doesn’t have much power.

Question- could I get a 12v inverter and power it off of my battery which is converted from AC? so it has more power instead of it not reaching the full 24v?

I have a gaming controller that started smelling of acetone. From what I could gather off google the battery is leaking. I need to order a new one but am having trouble finding an exact model. It is marked “ZY 702040 500mAh +3.7V 20230901” it has a red, black, and white wire coming out. All the ones on eBay don’t have the white wire. Will it still work the same without the white wire? I am not sure how to add photos this is my first post really. So I apologize in advance

https://preview.redd.it/a6x7ntag1iwc1.jpg?width=3024&format=pjpg&auto=webp&s=9e1ba927b912903cf9655e0858d41064c8783356

I have a cpap that I want to use while tent camping and want to be able to plug it into a USB battery pack. It seems like the inverters I'm looking at all use a cigarette lighter for your car. Is there something that would let me do this?

Batteries ! I am pretty much a newbie to this whole rechargeables thing. At least anything beyond NIMH AA and AAAs - been using them for a while (still have some Sanyo Eneloops).

I have some Orbtronic protected 18650s that I keep as backups to my emergency radio (I live in Florida). I also just bought a Wurkkos flashlight that contains a Wurkkos 18650 but I'm pretty sure it is unprotected because it is somewhat shorter than the Orbtronic ones.

My extremely limited knowledge of protected vs unprotected batteries is that protected is 'good' and unprotected is 'bad'. But now I am questioning that. Can someone educate me a little on this topic ? Should I always try to get the protected ones or does it really matter ?

They will get charged on an Xtar 8-bay VC8 Plus if that matters.

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Thanks in advance.

I have a new LifePO4 battery that came with a charger that outputs at 14.4v per battery manufacture specs. I’m planning on hooking the charger my bus bars.

My question is if I need to disconnect the 12v accessories I also have attached to the bars. Mainly, I have a very expensive Dometic cooler. My concern is the higher voltage damaging my equipment.

Sorry if this has already been covered. I just wasn’t able to find this exact concern elsewhere. I’ve certainly seen YouTube videos where it appears to remain connected but it’s hard to wrap my head around how that’s ok.

Hey.

I just bought the 12.8V 100AH Power Queen LiFePo4 battery on Amazon as a cpap power source and backup for camping and at home incase of power outages..

I also purchased a Noco Genius 10 charged/maintainer but decided after purchase to research a bit and found a couple threads here on reddit with complaints of the Noco lithium mode not being programmed specifically for LiFePo4 batteries and having a surge that causes the PQ battery BSM to trip which I don't like.

PQ support of course says buy their 20amp charger for $120 but it's out of stock, Batteries Plus here locally mentioned "Battery Tender" whi h I found a 5 Amp one that has a specific 12v LiFePo4 option and it's $100

looking for recommendations if any of you have experience with this battery or ones like it.

thank you!

Hello community,

Peukert's effect describes how a battery's capacity decreases as the rate of discharge increases. As a design and simulation student am I tempted to include this effect in my Excel calculation sheet for calculating UAV performance for a VTOL UAV

But soon after doing a test flight and after analyzing the UAV logs, I have found out that

1. Peukert's effect is not quite applicable when the aircraft is on cruise mode and the current drawn is less than the quoted capacity of the battery

2. And also there was no noticeable effect on the battery's performance in VTOL mode either.

So I am asking the community -

a. if applying Peukert's effect makes any sense in battery performance modeling for cases where current drawn is lower than the stated capacity

b.How can I effectively model peukert's effect.

Thanks and regards

I haven't used this type of cell before but I have had normal machine screws vibrate out of devices before, with normal screws I've successfully used Loctite but I'm not sure if this is a good idea in the end of the battery cells.

I have a small hand mixer that I use to mix instant coffee in the morning. It takes two AA batteries. I’ve had this little mixer for years and maybe every 3-4 months it would gradually slow down and the batteries would die. There are two Panasonic evoltas in there that have lasted for a year and are still at medium speed. My wife swears she hasn’t changed them but I can’t explain it… This has led me in two thought directions. Fun prank idea somewhere else and, is there a such thing as a longer lasting low energy AA,AAA…battery? Usually when i change the batteries in that mixer, the first 50 uses are super fast and it slows as the batteries lose juice. Any help is appreciated.

Does anyone here know if the magnetic fields around DC lithium ion batteries are the same or different than around DC lead acid ones?

Are any other frequencies emitted by either type during use or charging?

I am deciding between the 2 for a solar system. Thank you!!

Hi Smart People!

I have a newbie question. If I want to have a switch that changes the load between two different batteries is it OK to switch only the positive side and leave all the negatives connected?
My guess is yes; even if one battery's negative side is "floating" above the other's there can't be any current flowing as there is no circuit completed, even if the batteries are different types.
I do not want to connect the two in either series or parallel, and I can just charge them separately.

Attached my sketch to illustrate.

Thanks for any help or explanation!

https://preview.redd.it/zkt5znn3hawc1.png?width=1258&format=png&auto=webp&s=3af244d88f8cf96a65c71208b12a57c231ccd256

How many watts in a portable power bank should I buy? Looking for a portable battery I can use for a 32 inch TV. I want to be able to watch an entire football game while in the pool/jacuzzi. No other plugins.

Hello all

I was wondering if anyone could give me the eli5 version for the cutoff voltage for load testing UPS batteries.

What should my load tester max charge voltage be? What should my load tester cutoff voltage be?

Googling suggests 13.8 volts charge voltage and then it will do a CC test down to 10.5 volts at 1 amp load.

A 12 volt 5AH SLA battery will run for 5 hours at 1 amp down to 10.5 volts under load ?

I like using solar lights in my garden - motion detector, pathways, uplighting trees/shrubs, but also for decor pieces that I make. Some seem to last forever, some I need to replace batteries almost yearly. I prefer to replace batteries than toss the whole thing and buy a new one, even though some are odd sized (2/3AA) etc. Currently trying to replace 3.2V 18500 and 14500 sized. Batteries marketed for solar lights are 1500-3000mA; but if they're sold for RC toys, they're 500-1000mA, and much cheaper. Will the mA difference mean the lights won't be as bright? or stay on as many hours? or that they won't recharge as many times? Advice please! (it's frustrating to half to pay nearly as much for a new battery as for a whole new device...) Eventually I'll transition to low voltage lights for the paths etc, but can't use those for my home-made decorations...

Am waiting for a long range work truck.

I want LFP Batteries because..

1. They last 2-4 x longer than NMC batteries - I want a truck to last a long time

2. They fill to 100pct. I can use all the range.

Your take?

I'm specificly talking about AAA batteries, they just don't work. Once they run out they don't charge. Ever. I've tried duracell and panasonic as well as both duracell and panasonic chargers, neither system works out of the box. Is this like crypto currency a thing everyone believes but doesn't really work?

Now I know the tech exists, as my cordless drill works. But what gives with the AA/ AAA market? Is it a lie to get us to not only buy batteries but multiple charging systems until we give up and go back to disposable batteries?

I have assembled a 5S2P pack using 10 3Ah 30A VTC6 Murata cells. I am finding it difficult locating a suitable bms which imo should be rated 60A because of the 2P connection.

There are lots of 30A boards but not 60A. Or am I wrong with the 60A rating that I am proposing. The size of the board should be 85mm x 63mm.....standard i guess for the 5S2P configuration.

Can someone point me to a suitable bms. Any comment is appreciated. This is my first time on Reddit, so apologies if this is not the right way or place to do this.

Hello people, I see countless suggestions about charging your phone when it reaches 20% or 30% but I've never seen it backed up with facts. It's been proven that letting your battery die damages it, but what is the lowest it can go without causing real issues (there is always some degradation no matter what you do).

The reason I am asking is this, when charging a phone the two major factors that cause degradation is temperature and voltage. And the higher the state of charge of a battery the higher voltage when charging. So charging at lower levels should actually be less damaging. As this graphs shows the best efficiency is achieved when charging from 10%.

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https://preview.redd.it/bf2ls3i9f8wc1.png?width=1017&format=png&auto=webp&s=63a7eb2ca08fbc33024082c8923ba732e44d3b43

How can I check my phone's battery health? I'm using redmi notes 9s. lately the battery is draining too much