Asus EEEPC 900A battery with bad cells or not...

[ponteley]

Battery lasts only for a few minutes.
I opened it up, all 4 18650 cells show ~ 4.0 volts.
Not sure what else to test.

 

[eidairaman1]

Replace

 

[ponteley]

Battery or cells?

 

[eidairaman1]

Whole battery

 

[FreedomEclipse]

If youre smart with a soldering iron and remember the order or how the cells were wired then just replace the cell's with good Sanyo, Samsung or Panasonic cells. 3000 or 3400mah cells don't cost that much. I only buy Panasonic, Sanyo and or Samsung cells though. Everything else is junk that shops sell to go with vape units and they really suck and could catch fire or explode randomly

 

[ponteley]

If youre smart with a soldering iron and remember the order or how the cells were wired then just replace the cell's with good Sanyo, Samsung or Panasonic cells. 3000 or 3400mah cells don't cost that much. I only buy Panasonic, Sanyo and or Samsung cells though. Everything else is junk that shops sell to go with vape units and they really suck and could catch fire or explode randomly

So, even if all cells show a good charge, still replace them?

 

[eidairaman1]

So, even if all cells show a good charge, still replace them?

Yes because a meter cant load test them

 

[FreedomEclipse]

So, even if all cells show a good charge, still replace them?

Yes. Because the newer cells are Fresh and more than likely much higher capacity then the factory stock cells. So doing it this way isn't without its advantages. You'll get a significant increase in run time with the higher capacity batteries and you'll know what capacity and quality of cells you have put in. Buying a replacement battery pack from eBay or amazon won't tell you what's in it other than the total capacity and operating time. The seller could of rebuilt it with inferior sells before selling it on to you

Just remember that if you take this route then the new batteries will need to be cycled at least twice before they reach their full rated capacity and also so the chip connected to the battery package can calibrate itself so battery life might be a bit poo when they are charged for the first or second time

 

[lexluthermiester]

Battery lasts only for a few minutes.
I opened it up, all 4 18650 cells show ~ 4.0 volts.
Not sure what else to test.

Mate you're better off just buying a new battery.
https://www.amazon.com/Battery-Compatible-ASUS-701SD-701SDX/dp/B07P9H9F55
Or
https://www.amazon.com/Battery-Compatible-ASUS-701SD-701SDX/dp/B07P9HNG7S
depending on the color of your particular EeePC.
Or if you prefer Ebay;
https://www.ebay.com/itm/NEW-Batter...C-801-900-A22-700-A22-P701-BLACK/380438524988

 

[kastriot]

Just buy new battery don't waste money on half solutions.

 

[biffzinker]

If youre smart with a soldering iron

DO NOT hand solder Lithium cells the high temperature kills. Spot weld instead.

Edit: Covering the vent with solder is bad.

 

[lexluthermiester]

DO NOT hand solder Lithium cells the high temperature kills. Spot weld instead.
Edit: Covering the vent with solder is bad.

If lead/tin solder is used, a lower soldering iron temp can be set as long as proper flux and swift contact technique is used as well. This methodology can be used safely on Lithium-Ion batteries. Generally though, unless someone is very skilled, soldering on those types of batteries is risky.

 

[trog100]

a dud battery will still show the correct voltage fresh off a charge.. they lose capacity and will show full charge voltage even though there is nothing them..

you test them by applying a known load.. see how long they take to go flat relative to a known good one..

trog

 

[newtekie1]

a dud battery will still show the correct voltage fresh off a charge.. they lose capacity and will show full charge voltage even though there is nothing them..

you test them by applying a known load.. see how long they take to go flat relative to a known good one..

trog

Just what I was going to say. You need to test their capacity, not just the voltage after a fresh charge.

I use one of these: https://smile.amazon.com/dp/B07L3LVQN8/

 

[theFOoL]

For a netbook that old just replace the battery via eBay. That simple...

 

[Zareek]

If youre smart with a soldering iron and remember the order or how the cells were wired then just replace the cell's with good Sanyo, Samsung or Panasonic cells. 3000 or 3400mah cells don't cost that much. I only buy Panasonic, Sanyo and or Samsung cells though. Everything else is junk that shops sell to go with vape units and they really suck and could catch fire or explode randomly

He's right if you are going to do your own cells don't mess with the Chinese batteries. I also trust LG in addition to the list above. They make excellent Li Ion cells....

 

[ponteley]

Thank you everyone for replying. Replaced cells with another Sanyo 18650s that I harvested from good Dell battery. Now it's holding ~
2h charge

 

[Zareek]

Nice, I miss my Eee PC1005HA that machine was handy and fun. It got like 8-10 hours on a full charge. HDD failed several years ago. I think I tossed it in recycling.

 

[trog100]

For a netbook that old just replace the battery via eBay. That simple...

you can rebuild them using better cells than those found in ebay packs.. being as its already apart that is what i would do.. its not that difficult with small 4 cell pack..

 

[Bill_Bright]

The problem with soldering is to get a good solder joint, the jumper wires and the battery contacts themselves have to get up to proper temperature for the solder to properly bond. So I'm with biffzinker and spot welding is the only safe way to do this. While the welding does create much hotter temperatures, that very high temperature is concentrated in a much smaller "spot" and for a much shorter period of time. The heat just does not have enough time to spread into the cell itself. But soldering requires holding the very large (in comparison) solder tip on the battery contact for a long period of time. Not good. And since it is not likely you have a spot welder, replacing the batteries is the smart way to go.

Yes because a meter cant load test them

^^^This^^^

Like all power supplies (PSUs, car engines, motors, and batteries), to properly test them, they must be tested under a realistic load or loads. It is not uncommon for a battery to read full voltage only to drop significantly as soon as any load is applied. So unless you measured the voltage with the batteries in circuit and under load, you did not test them properly.

 

[trog100]

the thing is bill passing a load test dosnt tell the full story ether.. it has to be a given load for a given time.. the load and time being directly related to the batteries capacity and discharge rating..

batteries dont just die they wear out slowly with use.. basically the rated capacity slowly drops off with use and time.. there is only one way to properly test this.. apply a given load for a given time.. see how long it takes for the cell to go flat..

trog

 

[Bill_Bright]

the thing is bill passing a load test dosnt tell the full story ether.. it has to be a given load for a given time..

Very true too. But typically, if a battery is to fail (or drop below acceptable levels), it becomes apparent right away when put under a proper load - longer times just makes it more apparent.

A weak car battery, for example, will be apparent right away by turning the engine over slowly. You don't need to wait until it fails to turn it over at all to know it is failing.

But still trog is right - to fully test a battery, it must be under a proper and sustained load.

 

[trog100]

officially a battery is considered worn out when it gets to 80% of its as new capacity.. most people run them way past this.. basically a worn out battery for most folks is when it wont start the car engine..

a 90% worn out battery will do this.. he he.

however some applications need a more reliable battery that will always work.. imagine a super battle tank that wont start cos its battery is knackered.. that is when the 80% worn out factor comes in..

even a laptop that needs to run for 8 hours needs to go by the 80% as new factor..

what does amaze me is allowing for the fact we all now depend on batteries of some kind or other is just how little most folks know about the f-cking things..

trog

 

[R-T-B]

If youre smart with a soldering iron and remember the order or how the cells were wired then just replace the cell's with good Sanyo, Samsung or Panasonic cells. 3000 or 3400mah cells don't cost that much. I only buy Panasonic, Sanyo and or Samsung cells though. Everything else is junk that shops sell to go with vape units and they really suck and could catch fire or explode randomly

LG Chem has gotten quite good recently too in my experience. Otherwise, agree 100%

 

[Bill_Bright]

officially a battery is considered worn out when it gets to 80% of its as new capacity

Oh? I would like to see something "official" that claims that. Got a link?

I think it really depends on the application. I note the remote for my cable box doesn't start to yell at me until it gets down to 40%.

It also depends on the type of battery too. An alkaline battery, for example has a fairly linear decay rate - until dead. Many rechargeable batteries drop a little quickly, then stay flat for quite awhile, then drop off quickly. This is why AA rechargeables are typically rated at 1.2V when standard alkaline AA are rated at 1.5V.

what does amaze me is allowing for the fact we all now depend on batteries of some kind or other is just how little most folks know about the f-cking things..

That does not amaze or bother me. Consumers don't need to know that.

What amazes and bothers me is how most people don't think for a second about the hazardous waste old batteries present and the dangers they pose to land fills, oceans, and our children's futures. And I'm not even a tree-hugger.

FTR, Best Buy and most auto parts stores take old batteries for proper recycling and/or disposal. These include UPS batteries and CR2032 motherboard batteries, among others.