Oh, I thought more people would be interested in a li-ion level meter 
I think most people here are willing to make their own so they can have one with a number read out.
Its to expensive… Thais the Point.
If you buy a voltmeter from china, you can get a better performance for less…
I respect your work and will to share this but check this out http://www.ebay.de/itm/Mini-DC-0V-To-99-9V-Red-LED-Digital-Panel-Volt-Voltage-Meter-Voltmeter-/290717802952?pt=LH_DefaultDomain_0&hash=item43b021a1c8#ht_3833wt_952
Yeah… I am not chinese with large quantity of components, and $2 is barely the price of a LED bargraph…
I can reduce the price, but $2 don’t think about it.
The device is smaller, and more readable than just a voltage, that’s the point I stated at the beginning.
I updated the price.
Home made for under $10.
Yeah this is a voltmeter, this is just not the same.
The spectrum led battery meter costs $30.
So, it’s just the meter with two loose wires you have to manually hold onto while the battery is rolling around?
You dont get it…
Thats ok.
I will show you an integration of 2 of these devices into a WP2 II soon.
Not interested people please leave the topic in peace. Thank you.
I don’t get the difference? If the task is to find out the battery status than you can have this for a few bucks. There are a lot of such meters out there you have to compete with.
http://www.ebay.de/itm/new-Voltage-Indicator-Checker-Tester-1S-6S-Battery-/400337273964?pt=RC_Modellbau&hash=item5d35f6046c#ht_4644wt_1365
Like yours, it’s made for nimh but in 4.8v mode could work:
http://www.ebay.de/itm/RC-Model-7-LED-Battery-Voltage-Indicator-Monitor-4-8-6V-/300588824980?pt=RC_Modellbau&hash=item45fc7d7994#ht_2555wt_922
You see there are a lot out there, so it would be better to take one of these very cheap ones because they are in every detail better. Also a modification of one of the Chinese meters would make more sense than build a crappy thing up.
Sorry for opening your eyes but you have to see everything in context…
Guys if you want to discuss this type of thing do it in another thread. This is a sales thread NOT a discussion thread.
Silicon, sorry for my part in this.
This one is from 4.8v to 6v, doesnt work with 1 li-ion battery.
Thanks scaru.
No I Don’t, but I want to. I just need something more visual so I can see it in application. I’d like to see how it connects and works with a wP2 myself, and maybe it’s integration with a battery carrier. I’m not knocking it, I just want to see more detail pics of its usage and installment. I wouldn’t mind having something that shows me charging status on my SP2 while its running. Mine is just a voltage meter for testing after the fact. Would it be complicated for me to install? Help me out here.
Essentially what you would have to do is dissasemble the charger and then solder two wires onto the positive and negative. Then you have the wires lead out of the charger and mount the board wherever you want to.
I will show you some pics soon.
Before doing that I checked the whole internet to find the right one, none of them was what I was looking for.
The reasons I did this are,
- The device assesses from 3.3v/3.4v to 4.2v, which is the best range to check li-ion batteries, not from 3v to 4.2, etc. (I can configure it to change the range also, or for 2 batteries, etc…)
- It is small enough to be included in battery chargers.
- I can configure it to have 10 levels or 5 levels, which makes it smaller to integrate in battery chargers.
- I can implement 1 indicator for each slot in my WP2 II.
Ive never quite understood how that works. I always think it would just be showing the current running into the batteries from the charger when it’s turned on. How does it know. I love this kind of stuff, but I really need step by step visuals to try it myself.
It uses voltage not current. I'll explain exactly how later. :)
I wish I could stick one of these on my SRK
Here a diagram on measuring charge voltage v/s battery voltage is. I hope this helps. :)
It could hypothetically be done, you may need a CNC milling machine to mill the slots in it but not impossible. ;)
2 new pics with my 2 redilasts. This really shows that we get the level of the battery at a glance.
We can see right away if we are closer to 25, 50, or 75%. I can’t imagine an iphone showing the battery voltage instead of the remaining level, it would be very awkward…
Yeah i can see what you’re saying. Much nicer than a voltmeter, i think you would have to be a real nerd to have memorized what voltages equate to percentage of battery. I’ve got battery discharge graphs but my brain is to far gone to remember them. Where as that gives a instant read out.