I love my Kobo eReader, which I’ve had for quite a long time now. But I noticed that the battery life has degraded, to the point where I have to think about charging it.

Fortunately, this is an easy fix.

Taking the Kobo Clara HD apart

First, I used a suction cup and a plastic spudger to remove the back cover from the ereader.

It turns out that I need not have bothered, as I can do it quite easily with my fingers.

Replacing the battery

I used a plastic spudger to lift up and disconnect the white battery connector.

The old battery was attached with some double-sided tape and was easy to remove.

There was no useful information on the old battery to help me choose a new one, but I read online that I needed a “PR-285083” battery. Apparently, this is used in a lot of eReaders.

So I bought one from Amazon, on the basis that I could return it easily if it was not correct.

It was £15.

When the new battery arrived, I unplugged the old one and removed it, then plugged in the new battery.

I tested it before I stuck it in place, and it worked - it was half charged.

I also checked that it charged.

Once I knew it was working, I used some more double-sided tape to stick it in place.

I had to reset the time on the device after replacing the battery.

Increasing the storage

The Kobo Clara HD uses a micro SD card for storage. Mine was 8GB.

I bought a 128GB SanDisk card to replace it. I do not have anywhere close to that number of eBooks and, frankly, 8GB was plenty, but since I was tinkering with the machine, for the extra £10, it sort of made sense to me to increase the storage now anyway.

Backing up the old card image

I removed the micro SD card from the Kobo’s main board, and connected it to my laptop.

Using fdisk - l, I saw it was connected as /dev/sda, with three partitions.

I used dd to create an image of the whole device:

dd if=/dev/sda of=old_kobo_sd_card.img bs=4M status=progress

It took 411s, which was roughly as long as it took me to wrestle the new SD card out of its packaging.

You could probably use something like Etcher to do this, if you prefer a GUI.

Writing the backed up image to the new card

I used dd again to write the backed-up image to the new card (again using fdisk -l to check the location of the new card first):

dd if=old_kobo_sd_card.img of=/dev/sda bs=4M status=progress

Which resulted in:

7944011776 bytes (7.9 GB, 7.4 GiB) copied, 451 s, 17.6 MB/s
1895+0 records in
1895+0 records out
7948206080 bytes (7.9 GB, 7.4 GiB) copied, 592.371 s, 13.4 MB/s

Expanding the partition on the new card

I used gparted for this, expanding the third partition to use the remainder of the card.

I could probably have used the command line, but I did not.

Testing it

I popped the newly-flashed into my Kobo and it booted fine.

Unsurprisingly, it was identical to how it was with the old SD card.

Success!

In “Device information”, under “Onboard storage”, it says that I have 117.6GB of 118.0GB available, which should keep me going for a while…