In this video, I plucked a battery from a Honey Melon street crystal, ending up with another 500-milliamp hour battery to add to my growing collection. After checking the connection, I added a protective PCB and tested the battery - a reasonable 3.5 volts at a flat level. Following the safe soldering of wires and wrapping it up, I hooked the revamped battery to my charger. It showed promising results, charging quickly at one amp with voltage visibly on rise. After a full recharge, I performed a load test which unfortunately gave a disappointing 311 milliamp hour. It falls short of my other salvaged batteries – 500 and 550 milliamp hour, but nonetheless, it’s a fine addition to the collection.
[0:00] so I found another thing from the street
[0:02] say crystal Honey Melon so let’s get
[0:06] this open and see what kind of battery
[0:08] it’s got inside so that should be fairly
[0:10] straightforward looks like this just um
[0:13] Clips on the end so let’s try and get
[0:16] into this
[0:23] so that’s the end cap removed
[0:32] this is the empty plastic tube
[0:36] I can see a battery in there
[0:38] so let’s pop that off
[0:41] here’s all the gunky stuff
[0:43] maybe we can just push this out let’s
[0:46] find a screwdriver
[0:52] so there we go and we’ll
[0:56] snip off the bit we don’t want
[0:59] um
[0:59] so let’s get rid of this
[1:05] and we’ll dispose of that
[1:09] and we also don’t need this piece either
[1:13] foreign
[1:24] and we’ll see what size of battery we’ve
[1:26] managed to find
[1:35] so we’ve scored another 500 milliamp
[1:38] hour battery so that’s not too bad I’ll
[1:42] add that to my collection
[1:44] now one of the things about these
[1:45] batteries when you Salvage them is they
[1:48] don’t come with any protection circuitry
[1:49] so let’s add on a protection PCB and
[1:53] this will be a nice battery we can use
[1:54] in our future projects so I thought
[1:56] before we do anything let’s just check
[1:57] to make sure that um red is red and
[2:01] black is black because often they seem
[2:04] to be swapped around so
[2:06] you can also check our battery voltage
[2:08] as well so let’s see what we’ve got
[2:15] that seems pretty reasonable 3.5 volts
[2:17] it’s pretty flat we’ll try charging it
[2:19] up once I’ve connected the battery
[2:20] protection
[2:23] so I’ve got my little battery protection
[2:25] PCB
[2:26] so the first thing I’ll do is just tack
[2:28] some wires onto the P plus and the P
[2:30] minus
[2:36] so that’s probably good enough
[2:39] now let’s remove these old wires from
[2:41] the battery terminals
[2:46] and we’ll just put a solder onto here
[2:50] take this it stops wobbling around
[2:52] because that’s getting a bit annoying
[2:55] okay it’s nicely joined on of course
[2:59] we’re doing to the wrong end
[3:04] try that again
[3:06] so battery minus to battery minus this
[3:09] time
[3:13] okay now we just need to do the plus so
[3:16] Battery Plus to positive
[3:20] okay
[3:21] so if we just heat this up we should
[3:24] weld together
[3:26] I think that’s pretty good
[3:29] so all we need to do now is wrap this up
[3:31] with some Captain tape and we’ve got a
[3:33] nice little battery
[3:36] so I’ve wired up to a little battery
[3:37] charger let’s see if it actually charges
[3:41] well that’s pretty promising
[3:43] charging pretty quickly at one amp and
[3:46] you can see the voltage going up so this
[3:48] battery looks perfectly decent so I’ll
[3:50] leave it to charge and then we’ll test
[3:52] the capacity so charging is complete
[3:55] let’s see what voltage we’ve got
[4:03] oh there we go pretty much 4.2 volts so
[4:06] not bad at all so I’ll do a load test
[4:08] and see how much capacity we’ve actually
[4:10] got so it’s hooked into my load tester
[4:12] we’ll just try discharging it at half an
[4:15] amp and um
[4:16] See Your Capacity we get
[4:19] into
[4:21] reset this which I can’t remember how to
[4:23] do it
[4:27] nope
[4:31] there we go
[4:33] clear data
[4:35] okay that doesn’t seem to add anything
[4:37] our capacity still says that
[4:39] um
[4:41] try
[4:46] I know there’s some way of doing this
[4:51] okay so it turns out you have to remove
[4:54] the input voltage before you can clear
[4:57] it down so let’s try that again
[5:00] so
[5:01] we’ll start the discharge and we’ll see
[5:04] how long this battery lasts for and what
[5:06] capacity we get well that’s a
[5:08] disappointing it’s only 311 milliamp
[5:11] hours
[5:11] these other batteries I sell I’ve
[5:14] salvaged previously this one’s a 500
[5:16] milliamp hour battery
[5:18] and this one’s a 550. they both tested
[5:22] um full capacity so what I might do is
[5:25] um charge this one up again and do
[5:28] another test and just see how well it
[5:30] does but even at 300 milliamp hours it’s
[5:33] still not bad so I’ll be adding it to my
[5:35] collection