This battery was sent by Kim Sleep, who's sent a few other items in the past. It's a rechargeable PP3 style 9V battery that has a built in micro USB charging connector and a generous lithium battery that gives the unit a capacity of around 400mAh at 9V.
The use of a boost circuit to step the voltage up to 9V means that it remains at that level for the full discharge until the lithium cell's protection circuitry shuts it off.
When I had the unit open I intuitively resoldered the connection between the two parallel cells, as it looked a bit dry.
Russ Wigglesworth sent a link to a full battery test where one of two batteries had only half capacity, suggesting that the solder connection between the two cells was not intact.
http://budgetlightforum.com/node/51493
If you have a battery and it seems to have half capacity I'd recommend opening it in a half charge state (to minimise cell voltage differential) and very carefully testing both cell voltages. If they are different, then the cells may not be connected together properly. They will need to be at a similar voltage before resoldering them.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
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The use of a boost circuit to step the voltage up to 9V means that it remains at that level for the full discharge until the lithium cell's protection circuitry shuts it off.
When I had the unit open I intuitively resoldered the connection between the two parallel cells, as it looked a bit dry.
Russ Wigglesworth sent a link to a full battery test where one of two batteries had only half capacity, suggesting that the solder connection between the two cells was not intact.
http://budgetlightforum.com/node/51493
If you have a battery and it seems to have half capacity I'd recommend opening it in a half charge state (to minimise cell voltage differential) and very carefully testing both cell voltages. If they are different, then the cells may not be connected together properly. They will need to be at a similar voltage before resoldering them.
If you enjoy these videos you can help support the channel with a dollar for coffee, cookies and random gadgets for disassembly at:-
http://www.bigclive.com/coffee.htm
This also keeps the channel independent of YouTube's advertising algorithms allowing it to be a bit more dangerous and naughty.
Vos explications sont excellentes 'as usual'. Bravo, keep the excellent work up.
Ordered a newer version and the circuitry, charging port and the terminals are all at the same end.
3yrs later, if it had an on/off switch, it could be kept charged until it's used. Maybe bring out 2 wires? I just bought some of these and forgot about the constant current draw.
You know quite a bit about electronics circuitry. I wonder if you kNow the answer to a question I've been pondering.
If you have the rechargeable battery installed in a device and you have the battery connected via the charging cable whilst charging. Will this cause any damage to the device?
I was just trying to be lazy and thought if the rechargeable batteries are always being charged while it's in the device there wouldn't be any down time while batteries needed to be charged?
What is the self discharge? I want to use in a multimeter that often times i don't use and i don't want to find it every time dead
So, these have boost converters inside – making it output constant 9V independant of charge status, and then suddenly switching off due to battery protection circuit. This shouldn't be used in smoke detectors, then, since they wouldn't be able to detect low charge any more, right?
These type of 9V batteries would therefore have a maximum capacity of 1000 mAh ? Realistically speaking. ๐ค๐
Because on AliExpress they are selling them for rediculous capacities (like 6800 mAh, 12800 mAh…). ๐
the ni-mh 9v rechargable i have is of the 7s variety. most electronics i've used it in don't complain but the multi cell series design seems to make it far less shelf stable than the single cell aa and aaa batteries
Have you seen the 1.5v li ion AAs? Are they any good. I'd presume a similar, if opposite function circuit inside. Can they really be 2500mah?
Cheers.
Is it ok to Connect a 12v5w solarpanel directly to it? To load the battery?
Benim dรผลรผndรผฤรผm dizayn ๐
Pls do a video on how to make diy a rechargable 9v battery .tq
I like it, it could be a nice use for multimeters. Not that I need to replace the battery every two weeks on mine but I hate the waste and the fact that I have to go and buy a new disposable battery
Side note, don't use these to power guitars with active pickups or active EQ. Found out the hard way with lots of fizzy noise only when using one of these batteries. Seems to work fine in the Wah pedal though, I guess the power rail never gets near the audio path in a crybaby!