Tagged Questions
0
votes
1answer
54 views
Charging 12V/4A battery
Can I charge a 12V/4Ah sealed rechargeable battery with a 13.5V/500mA charger? If so, how much time would I need to charge it to 100%? If not, how can I charge the battery?
-4
votes
0answers
49 views
How many D cell batteries would you need to replace a 6V 4.5Ah battery used in a WAL? [duplicate]
How many D cell batteries would you need to replace a 6V 4.5Ah battery?
I'm trying to make a power comparison and not physically make the replacement. Would you suggest a different battery to compare ...
0
votes
1answer
64 views
Battery charger for AA batteries
I am looking for a battery charger for AA batteries, without taking out the batteries from the board.
The board which is powered by AA batteries is : ...
5
votes
2answers
197 views
Limit the current being absorbed by a battery
I have a generator that supplies a constant DC 10A current to a NiMH battery pack with 240 cells in series (nominal voltage of DC 288V). This current is too high for any cell once it has reached 100% ...
1
vote
1answer
70 views
Can leaving rechargeable batteries in the unplugged charger for a few weeks cause batteries to lose their charge?
Is it okay to leave rechargeable batteries in charger even if it's not plugged in?
2
votes
0answers
74 views
Are “wider” battery packs less at risk for polarity reversal?
If make a 5V battery pack as a series of four 1.2V NiMH batteries, there is some risk of polarity reversal when the pack is discharged too much. I doubt this risk is reduced by plugging such packs in ...
4
votes
2answers
106 views
How can charge be determined?
How can software determine the amount of power or charge left in a battery (like an iPhone battery or a laptop battery)?
6
votes
3answers
262 views
NiMh or LiPo batteries for unattended charging/usage
I'm in the planning stage of a summer project: A WiFi controlled robot for remotely monitoring a shore home. The robot will consist of a 4-wheel platform (4 motors, 1 A stall current each, 7 V), ...
1
vote
1answer
51 views
Lithium Ion charging problems - power outages
Does any one know if general charge circuits for lithium ion batteries suffer from this problem:
-Flat Battery put on to charge.
-A power outage of long duration occurs (say 8 hours).
-When power ...
-3
votes
1answer
74 views
calculating the battery amperes to connect with UPS?
I have 500 watt UPS, which outputs 220v and 50Hz. The calculation says that I need 500/12v = 41.67 Ampere and 12v battery to use with this UPS. But mostly people around me suggested 120A/h battery. ...
1
vote
2answers
116 views
Mosfets as a switch for batteries in series
I am contemplating a way to build a new battery pack for a project that I am working on. However I think that I have run into a problem, but I am not sure.
I have a battery pack with about 27 ...
0
votes
2answers
57 views
Why is this electro motor going slower?
From an old dust buster I've got this electro motor, the included battery pack and the charger:
I ripped everything apart (the dust buster was broken) and the motor still works. After playing ...
-3
votes
1answer
60 views
Is my battery indeed has 12 cells/7800mAh? [closed]
I've ordered 12 cell 7200mAh battery for my notebook HP HDX18t. When I received the battery it says 14.4V/7800mAh ( and not 7200mAh like it was stated).
1 - According to this site the number of ...
1
vote
1answer
60 views
Battery Profiling Device
I am working on building a battery pack for a solar car. I need to know if there is a device on the market that will "profile" the batteries (lifepo4) that I have, so that I can put like batteries ...
0
votes
0answers
62 views
MCP 73213 battery charging IC
I am using MCP73213-A6S/MF IC to charge 2 Nokia BL-5C battery which are connected in series. The fast charging current of this battery is 1020 mA. Please let me know the type of adapter to be used to ...
-4
votes
4answers
487 views
Can a phone charger be adapted to charge a laptop battery? [closed]
I've obtained a laptop that has no charger. Short of buying another charger online, can a phone charger be adapted to charge the laptop's battery, provided it's disconnected from the laptop (i.e., the ...
2
votes
2answers
93 views
Battery Charging Current Determination
When charging a battery using a solar panel, or even another battery, how is the current flowing through the battery determined?
Will the internal resistance of the battery draw a certain amount ...
-3
votes
1answer
126 views
How high charging temperature causes damage to AA size NiMH cell
I used a portable thermometer and put on top of a battery charger. I notice that the temperature reach 39 degree Celsius and I can feel the warmth when I put my hand on top of the charger & the ...
2
votes
2answers
118 views
How fast may I trickle charge a full LSD NiMH battery?
I've bought two packages of low-self-discharge nickel-metal hydride AA batteries, each made by a different well-known battery manufacturer.
Sadly, the datasheets aren't very detailed:
• One ...
2
votes
2answers
124 views
Need help designing a custom box
I am doing a hobby project and I don't know much about engineering; therefore I decided to ask pros.
I have a 12v electric device that runs on Car battery only and I need to make it work if there is ...
1
vote
0answers
50 views
How to design and build intelligent controller for a power pack made of recycled lead-acid batteries?
I am quite ignorant in electronics, but I am now building a small off-the-grid installation to be freely cloned (CC-BY) in rural areas of Eastern Poland (and perhaps Ukraine). The vital part of it is ...
1
vote
1answer
75 views
Spec'ing an always-on alarm/tracker for a car battery
What is the specification of a standard car battery (e.g. of a 2008 Jetta)?
Say, I want to connect an always-on alarm or a tracker to the electrical system of the car.
Is it likely to deplete the ...
1
vote
2answers
149 views
Why using short traces with the MCP73831 LiPo charger?
I'd like to use an MCP73831 to charge my lipoly battery. In section 6.2 I see they recommend short wires to the battery.
I bought my battery with wires, 20 gauge and approximately 30cm long. The ...
3
votes
1answer
141 views
Battery Charging - Electrical Model
A common technique used in battery charging algorithms is Constant Current / Constant Voltage. That is to say, initially a battery is charged by applying a constant current (which I believe is what is ...
6
votes
1answer
224 views
Intelligently Charging and Profiling Lithium Polymer Battery Packs
Lithium Polymer battery packs are widely used in Radio Controlled (RC) airplanes among other things for their charge/weight advantages. These packs typically consist of X series cells and Y parallel ...
1
vote
1answer
203 views
charging battery while under load
my question applies to NiCd/NiMh battery types.
Can I simultaneously charge & discharge the battery? Might it cause any harm to it?
I presume there will be opposite movements of the charged ...
1
vote
1answer
195 views
How to charge backup battery with single regulator?
Having single LM1117 regulator for 3V, how can I charge it whenever there is Vin and protect ...
1
vote
1answer
237 views
Can I safely and efficiently connect batteries parallel to a DC source? [duplicate]
I'm building a custom radio system for a friend by using a car-audio setup built into a boom-box-like container. I have everything wired up, and it works well enough. In testing though, I've run into ...
0
votes
2answers
93 views
Obtaining and loading a battery chart
I am using a lead-acid battery in a solar charging system. I am writing for an ATMEGA328 to determine the state of charge of the battery. Its my understanding that this will require a sort of data ...
0
votes
1answer
355 views
Making an extended Battery Pack + Charger for a Tablet PC
I want to make a battery pack with mains charger to power my tablet that has a wonky battery. It lasts all day if I do not use WiFi, but with WiFi it dies within the hour.
I have 4 Nokia BL-5C 3.7 V ...
-1
votes
1answer
335 views
Charger specification of 3000mah battery
I am planning on making a USB charger for my Tablet whose battery is of 3000mah. What should be the output current and voltage required for the charger? Is there anything else other than the output ...
0
votes
1answer
178 views
Can i have 3X3.7volts Nokia BL5c added?
How do i combine 3 × 3.7V Nokia BL5c batteries to make 11.1 volts and 3060 mAh?
I was thinking to use the above configuration to power up a laptop. Also, is it feasible to use a higher 3060 mAh ...
2
votes
1answer
122 views
Can a lead-acid battery charger be used for “Gel” type?
I have a PB-600-24 lead acid battery charger.
Can I use it for the battery type that has an image as below? 4 of the batteries are in series.
6
votes
1answer
434 views
LiPo vs. NiMH for kid's toy
I've been researching here and on google regarding potential battery technologies for a toy that I want to make for my kids. I was hoping to get others' perspectives on this, keeping in mind that ...
2
votes
2answers
195 views
Are there any dangers to consider when replacing a permanent AA NiMH battery?
The battery in my electric razor has failed to charge for several years. It does not turn on unless I leave it plugged in for 20 minutes and it turns off immediately if I unplug it. To save some ...
7
votes
1answer
160 views
Before storage why should a Lithium Polymer battery be charged up to only 40-60%
While storing a Lithium Polymer battery cell or a device with a Lithium Polymer battery why should we make sure to discharge the battery to 40-60% (and only then put it to storage)?
What happens if ...
2
votes
2answers
479 views
3.7 Volt external battery to charge a another 3.7 Volt Phone Battery?
I would like to know if a 3.7 V external Battery would be able to charge a phone battery of the same voltage. From my understanding, the batteries would charge each other until the charge in both the ...
5
votes
3answers
1k views
Measure Lithium ion battery voltage (thus remaining capacity)
What I am working with: I am running my self-made Arduino board (in the sense that I use the Arduino bootloader and code editor) at 3.3V, and powered from a Lithium ion battery, which is USB-charged ...
5
votes
4answers
934 views
When using a Laptop, is it desirable to keep it charged from the Mains all the time?
While using laptop I usually plug in my Laptop charger (i.e., from Mains power).
What is more effective - to keep Laptop plugged in at all times when possible, or some other approach (e.g., running ...
2
votes
2answers
161 views
How to choose Li-ion or other battery for uC (packed into thin small device) and connect
Can we connect Li-ion batteries to microcontroller?
If yes how? How to choose a battery - what are the requirements? Are there battery chargers seperately for Li ion?
I am aking a small device ...
1
vote
1answer
3k views
What should the voltage of a fully charged lead acid battery be?
I don't have a proper lead acid battery charger... But I own a small Yuasa 7Ah battery. I am using a 13volt 1.5A wall wart to charge it. And I have a volt-meter to check the voltage.
At what ...
4
votes
2answers
656 views
How can I safely charge multiple deep cycle batteries simultaneously?
I work at a car auction and we use deep cycle marine batteries with booster cables attached to hand trucks to wheel around the lot for boosting cars. I've been told by our battery distributor the ...
0
votes
1answer
77 views
which battery will supply the load?
I have connected 14V supply terminal from alternator to 12V battery terminal and has taken the load across these terminals . But the load is operating still in 12V, and when measured across the ...
6
votes
2answers
1k views
Can I charge a 12v sealed lead acid with an old wall-wart (not made for charging)?
Will it hurt the battery? If I left it overnight would I run the risk of "exploding" the battery?
I have a 7Ah SLA battery that I need to charge, but I don't have a charger and I don't want rake out ...
0
votes
1answer
210 views
Can I recharge 12V batteries individually while why are attached in series? [duplicate]
Possible Duplicate:
Charging two lead-acid batteries connected in series, separately (with two solar panels)
I have 12V Solar Panels and 12V batteries. But my laptop needs 17V to recharge. ...
1
vote
4answers
405 views
Charging two lead-acid batteries connected in series, separately (with one solar panel)
I have 2 sets of 2 lead-acid batteries connected in series to produce 48V. They are powering an audio amplifier.
I'd like to be able to charge them with ONE solar panel. If I connect the output of ...
3
votes
1answer
1k views
Smart charging circuit for NiMH battery pack
I want to build a solar powered charger for a niMh battery pack to run a microcontroller. What are the fundamentals of building a smart circuit that will not overcharge the battery and will also allow ...
5
votes
1answer
496 views
How to make a balanced battery pack?
I am making a robot for my workplace right now. I started with a 20servo kit. It came with a really terrible 10.6volt, 800mAh NiMh battery pack though.
I would like to make a lithium pack for ...
3
votes
3answers
127 views
How can I measure the charge of a rechargeable cell?
I'm using a bluetooth keyboard which need four AAA batteries. After the cells are charged (at least according to the charger), the keyboard still doesn't work properly; there is a green LED that ...
5
votes
1answer
355 views
Charging two lead-acid batteries connected in series, separately (with two solar panels)
I have two lead-acid batteries connected in series to produce 24V. They are powering an audio amplifier.
I'd like to be able to charge them while they are powering the amplifier, with solar panels.
...
