It turned out that after a year and a half in the off state, the battery of the iRobot robot vacuum cleaner "kills itself", and it is no longer possible to restore it without disassembling the battery. Well, I took it apart and rebuilt it.
It so happened that the iRobot Roomba i7 + robot vacuum cleaner was not used for a long time. When I tried to turn it on, there were no signs of life. I removed the bottom cover (for this you need to remove the side brush and unscrew the four screws).
The battery occupies half of the compartment (this is done so that you can install a battery with twice the capacity).
The battery voltage was less than a volt. I had to open it. The whole structure is non-separable, but if you really want to, you can disassemble it. The lid is held by a micro latch along the entire contour. With the help of a knife, we managed to slowly remove the lid, breaking most of the thin surface of the latch, but there is nothing wrong with that - the rest holds the lid normally.
It is also not so easy to pull out the batteries in the cassette from the case - the cassette is held on by four latches in the depth. They can be bent relatively easily with four thin objects inserted into the slots between the cassette and the case.
The voltage on each of the four cans was about 1.5 volts - it seems that "woe happened to the battery crazy" - his smart circuit that protects banks from overdischarge and controls the charge is also a bit consumes. For a year and a half, she consumed all the energy of the batteries, turned off the output and continued to slowly eat up the batteries. At the same time, the battery could no longer be charged by regular means.
The iMAX charger refused to charge the battery, reporting too low voltage, so I just connected the laboratory source power supply directly to the banks (minus to the output TV1, plus to TV5), set the voltage to 16.8V (4.2x4), current 1A and the batteries were charged as if nothing happened.
Moreover, the balancing circuit of the board also balanced them - the voltage on the banks after charging is 4.2 V + -0.01V.
I collected everything back, put the vacuum cleaner on the base and it immediately came to life. Works, cleans up. Now the main thing is not to leave it without charging for more than six months.
Video:
https://www.youtube.com/watch? v=W6AHIl8bqVs
Peace for everyone!
© 2022, Alexey Nadezhin
For twelve years I have been writing about technology, discounts, interesting places and events. Read my blog site ammo1.ru, in Learn, Zen, Mirtesen, Telegram.
My projects:
lamptest.ru. I test LED lamps and help you figure out which ones are good and which are not so good.
Elerus.ru. I collect information about domestic electronic devices for personal use and share it.
You can contact me in the Telegram group @ammochat.
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