Knowledge Base
Community

Bosch 509e battery pack rebuild

Started by: sheddi
On: 10/03/2012 | 16:58
Replies: 20
Reply

by: sheddi
on: 10/03/2012 | 16:58 edited: 10/03/2012 | 16:59

Bosch 509e battery pack rebuild

Because everyone needs a hobby ...

 

Hi folks. While I am willing to accept that I'm the only person here who's bothered about rebuilding a Bosch 509e battery pack, the basic principles should apply to all the old-school phones with NiMH batteries.

 

So, without further ado, let's get our hands dirty.

 

Required:

1. Duff Bosch 509e battery pack.

2. Replacement 3xAAA battery pack. Mine came from eBay, was meant for a cordless phone and cost £1.08 delivered from China.

3. Soldering iron and solder.

4. Sharp knife and small screwdriver (I used a Swiss Army Knife for both).

 

Optional:

5. The rest of the Bosch 509e Smiley Happy

6. Sticky stuff remover

7. Copious quantities of tea ...

 

Step 1:

Here's my beautiful Bosch 509e.

1. Start here., Here's my lovely Bosch 509e. Perfect working order, but the battery won't hold a charge.

 

Step 2:

Remove the battery pack. You can see the 3 600mAh NiMH AAA cells within.

2. The battery pack., Here's the battery pack removed. Clearly visible are the three 600mAh NiMH AAA cells that make up the pack.

 

 Step 3:

Carefully, using a pocket knife or a flat-bladed screwdriver, prise loose the plastic cover to reveal the cells and the little PCB with the contacts.

 Run a knife blade behind the cells to separate them from the case (they're stuck in with some adhesive foam) and lift them out. Clean up the case to your own standards (this is where the sticky stuff remover comes in handy).

 

Step 4:

Here is my replacement 3.6V 800mAh cordless phone battery pack, bought off eBay from China for £1.08. Usefully it's got 33% more capacity than the original 600mAh cells.

4. The replacement battery, A 3.6V 800mAh cordless phone battery pack, bought off eBay from China for £1.16. Usefully it's got 33% more capacity than the original 600mAh cells.

 Remove the outer heatshrink from the battery pack (being careful not to damage the insulation on the cells), trim the leads to length and solder on the little PCB with the battery pack contacts. Make sure you get the polarity of the connections right, or it could all go horribly wrong later!

 

Step 5:

In the immortal words of the Haynes manuals, reassembly is the reverse of removal.

 Put the battery (centre) into the case (left) then refit the cover (right). I suggest you try it like this before you break out the glue, just in case you've got something wrong somewhere.

 

Step 6:

It should now look like this.

6. The finished pack., See, you'd never know it's been apart.

 You'd never know it has been apart, would you?

 

Step 7:

My creature, it lives!

7. My creature, it lives!, Switch it on and see if it works! As you can see I'm running it with an Orange SIM at present.

 Sorry for running an Orange SIM in the photo, I'll try to get another shot with a giffgaff one Smiley Happy

Giffgaff's company motto: Communication is our business, not our strong point.

Hanlon's razor: Never attribute to malice that which is adequately explained by stupidity.
To order a SIM from me (go on, you know you want to), click here: Get a free Giffgaff Sim
Message 1 of 21
by: exmember-2018-356361
on: 10/03/2012 | 18:02

I really enjoyed this guide!

 

Hope theres more! I enjoy fixing and taking things apart Smiley Happy

Message 3 of 21
by: ianhadling
on: 10/03/2012 | 18:18

Nice one! 

Like it!! 

Message 4 of 21
by: sheddi
on: 12/03/2012 | 21:06

Thanks for the positive feedback Smiley Happy

 

It all started with me being too cheap to spend £7+ on a replacement battery for a phone that's worth less than a fiver. Being able to see the NiMH cells through the battery case simply encouraged me.

 

I don't often have to fix phones, usually it's children's toys. Or cars. Or the washing machine. But next time there's a phone to fix, I'll be sure to take photos and share them here!

Giffgaff's company motto: Communication is our business, not our strong point.

Hanlon's razor: Never attribute to malice that which is adequately explained by stupidity.
To order a SIM from me (go on, you know you want to), click here: Get a free Giffgaff Sim
Message 6 of 21
by: drachir
on: 29/01/2015 | 15:36

I did a similar battery pack rebuild on the 509e, although the batteries I used came individually, with solderable tags welded on at each end. The idea of using a shrinkwrapped triple battery is much more elegant.

 

Compared to the original battery ratings, which were only 500 maH types, I improved the battery life to about a week... although that's all ancient history now. I use an iPhone nowadays, so it's a nightly recharge for me.

Message 7 of 21
by: bava99
on: 29/01/2015 | 19:47
Defo for the engineers amongst us!
Message 8 of 21
by: dan1951
on: 29/02/2016 | 12:36

There are a few tiny resistors and a diode connected to some of the four output pins on the battery pack. Can you please give details of these and their connections?

Message 9 of 21
by: davidevans0000
on: 29/02/2016 | 13:14
nice one @dan1951 welcome to the giffgaff forum.
Get a free giffgaff Sim
Message 10 of 21