All Questions
26 questions
-2
votes
1
answer
154
views
How to build DIY home energy backup system (UPS) [closed]
I have a home in a countryside where grid power cuts off very often (3-5 times per week) for a few hours, especially in a winter time.
I came up an idea to make a backup system that will automatically ...
0
votes
1
answer
146
views
What is the "best" way to make a DIY 7 V rechargeable battery?
I have a device (the Wii "sensor" bar, basically an IR LED array) that the literature says takes 7 V. I can't find any battery offerings that come in 7 V, but many that are 3.7 V, so I am ...
- 243
2
votes
1
answer
89
views
Trying to heat up 32-gauge nicrome wire
I was trying to heat up a nicrome wire (32gauge) using a 21650 lithium battery, and I have charged it. I have used jumper wires to connect all and joined the nicrome using wire connecting joint. The ...
- 21
1
vote
1
answer
104
views
How to Test Battery Health in GRUNDIG VCP 3930 with a Multimeter, Arduino, or Raspberry Pi?
As a follow-up to this question, I own a GRUNDIG VCP 3930 vacuum cleaner (which uses a 25.2V, 2000mAh Li-ion battery) that has stopped charging properly. I am being told that the battery on this ...
- 243
0
votes
1
answer
600
views
Is my 4s2p pack connections correct?
I'm planning to build my 4S2P battery pack using 18650 lithium-ion battery cells. I need to make sure my connections and my battery pack is correct and safe before I make the connections. Here's the ...
- 3
0
votes
1
answer
141
views
Simple circuit to cut voltage below 14V
I would like to power a DIY bluetoothbox from a Bosch Professional 18v battery but they do not have a BMS as far as I know. So I need a way to cut off all energy drawn from the battery as soon as the ...
- 1
0
votes
0
answers
61
views
How to recell a 60 cell 36V battery pack?
So unfortunately a disgruntled ex-housemate put a screw through my friend's electric bike battery pack.
It has burst one cell so we're definitely not plugging it in.
I think I'm capable of replacing ...
3
votes
2
answers
2k
views
How to safely use Lithium-ion batteries in DIY projects?
Disclaimer: I am far from being an electrical engineer, I'm only a DIY enthusiast trying to stay safe.
I'm building a collection of sensors using little ESP-01 chips, but having them running free on ...
- 323
1
vote
2
answers
415
views
Mixing old and new Li-ion batteries in parallel: long term effects?
I have four lithium-ion APC batteries. They are all from the same facility and their condition seems to be alright.
I'd like to connect all of them together in parallel, but my question is this: Will ...
- 135
0
votes
1
answer
80
views
I need help with putting together a battery
I want to make a 14V, 5A battery out of DIY crystal cells. Each cell is about 1.5V and 0.3A
I know I can connect on series until I get my desired voltage, but I need to increase the amps.
Is there a ...
1
vote
1
answer
962
views
DIY protection board for lithium-ion batteries. How to scale a schematic?
I need to build a DIY protection board for a university project. We are not allowed to buy one online so I have to construct it myself.
I have found a variety of schematics accomplishing the same ...
- 21
1
vote
1
answer
2k
views
Off-grid solar panel setup for estimated 15kWh daily consumption
I am planning to setup an off-grid solar panel system.
I've read Off-grid solar setup, but I am looking for clarification on my understanding on how to go about it in the most cost-efficient way.
I ...
- 75
0
votes
0
answers
152
views
DIY electronics projects powered by Sony NPF batteries
I'm looking into making some DIY projects to be powered by the Sony NPF series of batteries. These batteries are usually found in photography and video equipment.
The issue is I can't seem to find ...
- 69
1
vote
0
answers
57
views
Electrical energy transformation
I'm working on a DIY solar inverter.
The goal is to make the battery connected to it rechargable by both energy from solar panels and AC mains (if there is power supply.)
My battery is 24V DC, AC main ...
- 21
0
votes
1
answer
80
views
What type of battery is this?
I want to start this DIY project. According to the video, you need "2S 7.4volt battery and DC jack". What battery is this?
https://www.youtube.com/watch?v=cpdjQ0gheDQ&feature=youtu.be&...
- 205
0
votes
0
answers
73
views
BMS battery build DIY help
I am making a battery charger for a speaker using 4 18650 3.7V batteries.
Now I know that I would need to get a 4S Lipo or Li-ion PCB, the only thing I don't understand is the current rating that I ...
- 211
0
votes
1
answer
56
views
Replace UR battery by IMR with lower mAh [closed]
I am replacing a shaver’s battery, a Braun Silk Epil 5.
It uses a Li-Ion battery manufactured by Sanyo for Braun.
According to my research it must be a UR Battery like the UR18500L :
...
- 11
0
votes
1
answer
3k
views
Identify these components for bluetooth speaker [closed]
I am wanting to make my own DIY bluetooth speaker (first time electronics project) and I have found several good Youtube videos on the topic. However when it comes to finding the actual parts, I am ...
- 123
-1
votes
1
answer
314
views
DIY battery from scratch. Is it possible? [closed]
Batteries are expensive. I want to be able to store about 30 kW worth, but even the cheapest kinds of batteries, like Lead-acid, or Salt Water batteries are too much. I've looked into reviving dead ...
7
votes
1
answer
45k
views
Diy 18650 4s battery pack [How to charge, how to build?]
I'm building a bluetooth portable speaker.
However, I have some questions about building my first 18650 battery pack.
I have 4 pcs of Panasonic unprotected NCR18650B 18650 3.7V 3400mAh.
My goal is to ...
- 71
2
votes
1
answer
169
views
Device power requirements
I am designing a device and I'm confused on calculating my total amperage required.
I have designed this device to have 3 main circuits in parallel that all take 5 V from the same power source:
...
- 21
7
votes
3
answers
2k
views
Schematic for a lipo battery bleeder overcharge protector
OK, so I am building a 12v (really 11.1v) 10000mah lipo battery. I am going to use it on campouts to run things like 12v fans and car chargers and run other high-current devices that couldn't be run ...
- 71
1
vote
1
answer
5k
views
Can I charge a 12V 2A NiCd battery with 18V 14.6A?
I have a 12V 2A NiCd battery which I want to charge. I have a power unit that puts out 18V 14.6A. Can I use it to charge it? Would the battery just draw the current it needs or would it always put ...
- 51
0
votes
1
answer
573
views
DIY battery Pack Cell amperage difference
I have individually tested the capacity of ten 18650 batteries with my iCharger 4010. My question is, how much ampacity difference is ok when packing them in parallel ? The following are the readings ...
- 51
1
vote
1
answer
1k
views
How charge custom Li-ion pack 36v 10s6p
I have 10x 6p 18650 batteries. 13AH.
I found a protection circuit.
My issue is that I don't know how to charge the batteries. I could use a power source but I got it from my school and it isn't mine.
...
- 11
2
votes
2
answers
362
views
Google Glass 3.5mm jack with battery neck strap
I'm thinking of improving my Google Glass by DIY building a micro usb to 3.5mm headphone jack with a battery connected to a neck strap out of parts from the internet.
I've already built the neck ...
- 53