Connecting Two Batteries To Power A Laptop

[JetsetBkk]

I bought a new battery for my Asus Ultrabook UX31A laptop because it was lasting for only about 2 hours.

I thought the new battery would last longer, and it did while playing only Youtube vidoes - about 4 hours.

 

But today I took it to a meeting and ran Skype, and it lasted for barely two hours.

So I was thinking, is there a way to connect both the old battery and the new one in parallel to get more duration.

 

The battery cable looks like this:

- so there are 8 cables that would need joining.

Or, if I could find the male and female connectors...

I could make a "combiner" adaptor and not cut any cables - just have a cable with a male and a female connector inside the laptop, both connected to an 8 core cable that runs outside the laptop to a second female connector for the second battery.

 

Has anyone done this or got a better way of using two batteries?

I would also like an idea of where to get these weird connectors if that is a solution.

 

[phoneguy702]

Connecting your old and new batteries together in that manner will only do damage to your new battery, It will give you some extended life because the parallel connection will ad Amp Hours, but because the batteries are miss matched it will not be the solution you are looking for.  You would be better served if you looked for a replacement battery with a larger AH (Amp Hour) rating than your present battery and that would still fit into your laptop.  Is it just too difficult to use the AC adapter?  Or possibly you could find an external battery with charging ability like the mobile phone external batteries.

[Metropolitian]

Instead of a combining adapter you could use the DC adapter input. Make a pack with that battery or other batteries with the right volt output and a cable to the DC jack where normally the AC adapter is connected.

You can then add a DC input on the external battery pack for the ac adapter to bypass and with the right electronics charge the battery pack.

 

Done such thing for the DV camera a long time ago, the battery ran out too fast and with the external battery pack I could record for hours.

[Metropolitian]

If you like DIY , check this:

 

https://www.overclock.net/forum/31-power-supplies/1470414-my-diy-10-hour-external-laptop-battery-pack.html

 

 

And

 

https://www.youtube.com/watch?v=ZQjazsiyr8s

 

 

btw. If your laptop has USB-C, big change you can charge/power feed your laptop from a powerbank and a usb-c cable.

 

[JetsetBkk]

1 hour ago, phoneguy702 said:

Is it just too difficult to use the AC adapter? 

I've had a look at all the links provided by others, reconsidered my approach and decided that your suggestion is probably the simplest! ????

 

And I'm getting too old to mess around with fiddly connectors etc, so I'll just pack the AC adaptor and an extension cable next week! Thanks for making the obvious suggestion!

 

[northsouthdevide]

If you wanted to join 2 batteries together, you would have to balance each individual cell. 

You would need some special equipment to do it. 

Its possible, but just to use on 1 laptop, you'd be better taking or sending it to a shop. 

If you search lithium battery on lazada, there's about 3 shops that I think can help you. 

The name of only 1 springs to mind, and that's baan lithium, but I think its in the south around phuket somewhere... 

There are a few more in the central area that would make a bigger battery for you. 

[OneMoreFarang]

This is the way lithium battery packs are wired.

The big connector is the main input/output. The small connector allows the charger to read the voltage of each individual cell. Obviously your connector might look different but the principle is the same.

If you would combine two packs in parallel then the charger would not be able to check, and balance, all individual cells anymore. Not good!

[Crossy]

If you really want to retain independence from the mains then there are plenty of 12V to 19V (or whatever your lappie needs) converters on AliExpress, just add some connectors and a 12V SLA or lithium battery of whatever capacity you're prepared to lug around with you.

 

Something like this although you need to verify what voltage and wattage your lappie needs 

https://www.aliexpress.com/item/32833328662.html

 

 

[KhunHeineken]

With my last three laptops, Acer, Asus, and HP, I could buy an extended battery, or high capacity battery, or some terminology like that. 

 

The batteries were a lot bigger, and either stuck out the back of the laptop, or stuck out the bottom of the laptop, making it sit up, which was better for typing.  These batteries gave a huge amount of run time to the laptops.   You may have to search a little for a part number, but there may be a factory made bigger battery for your laptop.

 

Also, one of the laptops that I owned, I forget which one, because I never bought it, had an accessory you could buy that was an adapter that allowed you to charge a battery by itself, not whilst in the laptop.  So, you could be using the laptop around a worksite, while the other battery was charging.  

 

Edited June 4, 2020 by KhunHeineken

[OneMoreFarang]

On 6/2/2020 at 5:18 AM, Crossy said:

If you really want to retain independence from the mains then there are plenty of 12V to 19V (or whatever your lappie needs) converters on AliExpress, just add some connectors and a 12V SLA or lithium battery of whatever capacity you're prepared to lug around with you.

 

Something like this although you need to verify what voltage and wattage your lappie needs 

https://www.aliexpress.com/item/32833328662.html

 

 

Maybe this will work. But please be aware that this might not work as expected.

These converters, like all converters, don't have a perfect DC output. They all will have ripple. And that might or might not be acceptable to the device with you want to power. Maybe you have to add some big and small capacitors to make it more smooth.

Here is an example:

 

Edited June 4, 2020 by OneMoreFarang

[Jan Dietz]

It'll work fine, the charge and power circuits in the laptop itself are designed to work with ripple from the standard cheap AC brick. 

Internally the main voltage will be 'mainly' used to top up the battery, so there it totally doesn't matter

It will then go through a bunch of DC/DC converters to reach the internal working voltages of 5V, 3.3V and 1.8V or less for the CPU/GPU. 

so plenty of headroom for a bit of ripple.

 

[l4ml4m]

hello, do you know if it is possible to an outside battery for a laptop that never moves ?

maybe a kind of UPS but flat, to put under the laptop ?

And would the laptop work if only connected to an external battery after removing the internal battery ?

 

thank you.