New answers tagged

1 vote

Windmills generate electricity by the spinning blades. Why can't EV vehicles recharge their batteries from their spinning wheels? Is that too hard?

The motion of a car is a form of energy, and to get the car moving in the first place that energy had to come from somewhere, either fuel or batteries. If your car is electric, energy stored in the ...
user avatar
  • 8,158
14 votes
Accepted

Windmills generate electricity by the spinning blades. Why can't EV vehicles recharge their batteries from their spinning wheels? Is that too hard?

They do. It's called regenerative braking. The only time you can practically recover energy from the wheels is during braking. Taking energy from them slows them down. If you do it while they are ...
user avatar
  • 4,385
1 vote

Li-ion battery overcharging

Battery protection ICs like the S-8261 are designed to disconnect the battery under fault conditions such as over-voltage during charging, over-current, short circuit or low voltage during discharge. ...
user avatar
  • 51.4k
-1 votes

12V solar panel voltage is not 12V in reality. How do I correct this? (ESP32 solar powered project)

When a battery is connected to a solar panel, the solar panel voltage is the battery voltage. This is a characteristic of electrical systems. When you connect things together, they have one voltage. ...
user avatar
  • 4,096
0 votes

Is taping a safe and effective way of connecting lithium ion batteries?

I would be very suspicious of 10 year old lithium laptop batteries. I've dealt with thousands of lithium ion batteries, 10 years would be seriously pushing the limits, usually you're lucky to get half ...
user avatar
  • 4,385
2 votes
Accepted

Is taping a safe and effective way of connecting lithium ion batteries?

That video is only good to show that wires can connect things. It is not a good way to connect batteries, especially if you need the pack to last. As the tape slides/stretches, then the contact ...
user avatar
  • 6,032
0 votes

Building a hybrid ultra-capacitor and battery bank

I would think that if the supercapacitor array is first in line and the battery banks after, sudden high amp drains can be serviced by the capacitor and the 'slower' amps from the batteries can ...
user avatar
  • 1
1 vote

How to wire a 13Amp UK plug for a type 2 electric vehicle charging cable?

I was in the same boat but I cut the plug off very carefully then used a gel filled waterproof conector to extend the cable so I didn't cut the small wires they looks to be something on the end but ...
user avatar
1 vote
Accepted

Understanding sporadic charging of a gravity battery

There's a problem with gravity batteries: When they generate power, the weight goes down at a somewhat constant velocity, which means the generator produces a counter-torque equivalent to the torque ...
user avatar
  • 59.4k
1 vote
Accepted

12V solar panel voltage is not 12V in reality. How do I correct this? (ESP32 solar powered project)

Yes, you need a "charge controller", but a specific type -- a MPPT charge controller. MPPT = Maximum Power Point Tracker. From googling MPPT, "An MPPT, or maximum power point tracker ...
user avatar
0 votes

Dual cell protection using DW01

As I have tested, it is possible to protect two cell using two DW01 circuit, each protecting one cell. On the above schematic I have wrongly connected the GND pin of IC. It should be connected to the -...
user avatar
  • 55
0 votes

What voltage to charge a single NiCd cell?

You don't use input voltage as the metric for charging NiCd. Best results are gained by discharging to 1 V/cell, then charging at constant current of 0.1 of the A-hr rating for 16 hours. That is, if ...
user avatar
-1 votes

Can I charge a lead acid battery with a lithium ion battery?

I have jump started cars using an 18 volt ryobi lithium battery, alligator clips, wires taped to lithium battery terminals ,30 seconds and ,voila, it starts .Easy to carry with you when travelling. ...
user avatar
0 votes

Battery Charging with Two Constant Current Power Supplies in Parallel

Would the total current supplied to the battery be the sum of both output currents? Yes. Each supply will output current until reaching its maximum output voltage. The total current going into the ...
user avatar
  • 51.4k
4 votes

Voltage doubler current halving

When C1 is switched across V_IN, it consumes current (charge) as it (re)charges. When C1 switches in series with V_IN (thus doubling it), it also consumes current from V_IN as it (dis)charges and ...
user avatar
  • 13.9k
0 votes

Calculate battery state of charge percentage

The table can be put into excel then choose the line of best fit (trendline) by choosing a polynomial of the 2d degree you get: y=0.2777x^2 - 5.9451x + 31.809 y being the percentage and x the voltage
user avatar
1 vote

NiMH reverse charged cells

You are right to be concerned. While a NiMH cell can be taken down to 0 V without damage, any reversal of polarity will cause irreversible damage to the cell. If the battery doesn't contain too many ...
user avatar
  • 142k
1 vote
Accepted

Is it safe to use this arrangement of charging NiMH batteries in series and then using them in parallel

In it's original form, it wasn't entirely safe (from the perspective of the batteries) for reasons given in the comments on it. I asked the same question in the Electronics Hobbyists Facebook group ...
user avatar
1 vote

What powerbank output params are required so that it actually charges another device?

Your question is off the rails a bit, because you want to know which USB powerbank can charge your laptop. This is akin to asking which one can run your dryer. They aren't big enough to do that job....
user avatar
0 votes

Is is safe to let my PWM charge my 12V battery at 14.8V?

Wet cell batteries can be overcharged, and benefit from it. Maintenance involves adding distilled/de-ionized water to the cells. Sealed cells, including gel cells, have a way of recycling water that ...
user avatar
  • 4,096
1 vote

Can I charge a 3.7V 150mAh LiPo battery from USB?

First, as people already noted, your "USB port" or "USB charger" are not Li-ion chargers, they are constant-voltage (5V) power supplies, maybe with some limitations. Your MP3 ...
user avatar
  • 37.4k
2 votes

Can I charge a 3.7V 150mAh LiPo battery from USB?

They had 150-190 mAh Li-Ion batteries. All I can find are Li-Po replacements. What you call "Li-Po" IS a Li-ion cell. It's a pouch Li-ion cell, but a Li-ion cell nonetheless. Can I charge ...
user avatar
2 votes

Is it safe to use this arrangement of charging NiMH batteries in series and then using them in parallel

It might be safe but the cells will likely suffer. It is probably safe in the sense that it won't burn your house down and if you follow the suggestions in the answer by jp314, it may work fairly well....
user avatar
  • 415
2 votes

Is it safe to use this arrangement of charging NiMH batteries in series and then using them in parallel

You need to ensure that the switch is 'break before make' -- i.e. when the switch is changing over; in the middle, you have all switches open, not all closed. Most simple SPST slide switches are like ...
user avatar
  • 13.9k
0 votes

Can I parallel charge with parallel batteries?

All you have to do is get a small screwdriver and where the positive side is use the screwdriver to gently lift the cathode and it will release gas and jump back up to your your respective V
user avatar
0 votes

Circuit design of backup power with rechargeable battery

Will this circuit work? Yes Will it work reliably over longer periods of time? Maybe... It depends! It will depend on your selection of components... Lead Acid Batteries can take small charging ...
user avatar
  • 1,581

Top 50 recent answers are included