Question Shoving extra batteries into an Ashida: could it work?

[ATatForTatzelwurm]

In Console Modding 101 instead of Wii because it's a theoretical.
NOTE: I've never built a portable before, and I'm waiting for parts to come in before I start my Ashida. I have no experience with soldering, wiring, or portablizing consoles yet.

Whenever I see finished Ashidas, I notice there's a lot of empty space left inside the handles. I've been wondering if that space could fit some small additional batteries, just to squeeze some more battery life into a single charge.

As long as the batteries are all running in parallel and the wires to provide the power/charge are suitable, it should result in each battery being drained slower and thus extending the battery life of all of them put together, right? Is there any reason why no one I've seen has ever tried to fit additional batteries into the handles of their Ashida?

(If someone has shoved extra batteries into the handles before, I'd love to see what they did and what additional batteries they used!)

(3/4: Minor edit to tags for ease of finding/organization)

 

[Stitches]

IIRC it's partly about cost, wiring simplicity, and weight. You totally could edit the shell to fit more cells in, and double your runtime but you'd be increasing the overall weight and shifting the balance when held.

As for combining different cell capacities, we don't recommend it. Even though they are in parallel and will discharge safely enough together, the load on the cells will not be uniformly distributed. The smaller cells will experience voltage drop faster from their lower capacity, leading to the larger cells having to do more work and create load balancing currents between the cells as they try to keep their output voltages matching. This is bad for the cells and for the PMS.

The bigger problem is charging. Attempting to charge cells of different ages and capacities on a single circuit can and will fuse or even grenade the cells. The cells don't have individual protections or charge monitoring, so if there's a problem with one cell, that cell could quickly damage the others.

We only recommend using cells of the same capacity, make, and age in a system.

 

[kolenot]

I would also consider that the charging time will also increase.
For me it's not worth going through the effort if I would also have to double the charging time for the batteries.

 

[ATatForTatzelwurm]

IIRC it's partly about cost, wiring simplicity, and weight. You totally could edit the shell to fit more cells in, and double your runtime but you'd be increasing the overall weight and shifting the balance when held.

As for combining different cell capacities, we don't recommend it. Even though they are in parallel and will discharge safely enough together, the load on the cells will not be uniformly distributed. The smaller cells will experience voltage drop faster from their lower capacity, leading to the larger cells having to do more work and create load balancing currents between the cells as they try to keep their output voltages matching. This is bad for the cells and for the PMS.

The bigger problem is charging. Attempting to charge cells of different ages and capacities on a single circuit can and will fuse or even grenade the cells. The cells don't have individual protections or charge monitoring, so if there's a problem with one cell, that cell could quickly damage the others.

We only recommend using cells of the same capacity, make, and age in a system.

Ahh, I didn't know charging batteries of different capacities together would damage them, I thought it was only the age and type (alkaline, LI-ion, etc) of batteries that mattered. All the information I found about discharging together amounted to "Eh, it'll work as long as everything's in parallel." I hadn't thought to look into the charging process since I assumed 'it'll be fine' was the same in reverse. I'm glad I asked in here.

I was willing to put in the extra work of learning the wiring and taking the measurements to DIY it out (with help from an irl friend who knows computers better than I do), and I didn't care about extra weight or fiddling with balance... but damaging the internals whether charging or playing is definitely a no-go. Thanks for the information!

I would also consider that the charging time will also increase.
For me it's not worth going through the effort if I would also have to double the charging time for the batteries.

I would've called it worth it! If I could, I would loaded my Ashida full of batteries like Aperture Science dumping bullets into turrets if it made the battery life longer lmao. Shame it won't work out, but a torchic can dream!

 

[Y2K]

Ahh, I didn't know charging batteries of different capacities together would damage them, I thought it was only the age and type (alkaline, LI-ion, etc) of batteries that mattered. All the information I found about discharging together amounted to "Eh, it'll work as long as everything's in parallel." I hadn't thought to look into the charging process since I assumed 'it'll be fine' was the same in reverse. I'm glad I asked in here.

I was willing to put in the extra work of learning the wiring and taking the measurements to DIY it out (with help from an irl friend who knows computers better than I do), and I didn't care about extra weight or fiddling with balance... but damaging the internals whether charging or playing is definitely a no-go. Thanks for the information!


I would've called it worth it! If I could, I would loaded my Ashida full of batteries like Aperture Science dumping bullets into turrets if it made the battery life longer lmao. Shame it won't work out, but a torchic can dream!

What you probably could do is fit 4 4000mAh 18650 cells inside the main body of the portable with some clever shell modifications, instead of the two 5000mAh 21700s the BOM calls for. This would net you 16000mAh instead of 10000mAh, a 60% increase. The drawback would be the added weight, but the balance should remain the same.
Alternatively you could switch to Vapcell F60 6000mAh 21700s and gain a free 20% increase over a standard Ashida.
One final thing you could try but would increase wiring complexity, is you could try the earlier suggestion of 4 18650s, plus add an additional two in the handles if they will fit, and have them all wired in parallel. The unit will be substantially heavier, the weight balance will change, and it'll be harder to wire, but you're looking at a 140% capacity increase, which is quite ridiculous for a Wii portable. Lot of people consider 4 4000mAh 18650s to be the sweet spot, so I would go with that personally. Would be fun to see regardless!

 

[ATatForTatzelwurm]

What you probably could do is fit 4 4000mAh 18650 cells inside the main body of the portable with some clever shell modifications, instead of the two 5000mAh 21700s the BOM calls for. This would net you 16000mAh instead of 10000mAh, a 60% increase. The drawback would be the added weight, but the balance should remain the same.
Alternatively you could switch to Vapcell F60 6000mAh 21700s and gain a free 20% increase over a standard Ashida.
One final thing you could try but would increase wiring complexity, is you could try the earlier suggestion of 4 18650s, plus add an additional two in the handles if they will fit, and have them all wired in parallel. The unit will be substantially heavier, the weight balance will change, and it'll be harder to wire, but you're looking at a 140% capacity increase, which is quite ridiculous for a Wii portable. Lot of people consider 4 4000mAh 18650s to be the sweet spot, so I would go with that personally. Would be fun to see regardless!

Holy mackerel, I absolutely want to see if I can fit an entire six 18650 cells inside this thing. A 140% capacity increase would be incredible! I really, really hope it's possible to squeeze the extra two into the handles. I have to at least try to do it once I get all my parts in, and a test shell to check measurements.

Even if it doesn't work out, the info on using four 18650 cells instead of two 21700 cells is still really helpful. Thank you for this wisdom!

 

[Y2K]

Holy mackerel, I absolutely want to see if I can fit an entire six 18650 cells inside this thing. A 140% capacity increase would be incredible! I really, really hope it's possible to squeeze the extra two into the handles. I have to at least try to do it once I get all my parts in, and a test shell to check measurements.

Even if it doesn't work out, the info on using four 18650 cells instead of two 21700 cells is still really helpful. Thank you for this wisdom!

No worries. You may have to get clever with the placement since there's not much more room all things considered. I think it could be doable but you may not be able to include battery contacts and instead may have to solder directly to the cells (only do this if you have a good soldering iron that can deliver the power needed extremely quickly, ideally don't do this at all) or get yourself a spot welder and some nickel strips and spot weld a pair of two together, leaving enough of a tab to solder to safely. Spot welders for batteries are really cheap these days, so that would be my suggestion if battery contacts are a no-go.

 

[ATatForTatzelwurm]

No worries. You may have to get clever with the placement since there's not much more room all things considered. I think it could be doable but you may not be able to include battery contacts and instead may have to solder directly to the cells (only do this if you have a good soldering iron that can deliver the power needed extremely quickly, ideally don't do this at all) or get yourself a spot welder and some nickel strips and spot weld a pair of two together, leaving enough of a tab to solder to safely. Spot welders for batteries are really cheap these days, so that would be my suggestion if battery contacts are a no-go.

I'll keep this in mind, thanks! Thankfully, all my soldering and/or welding will be done under the supervision of a more knowledgeable irl friend who has build computers but not consoles before, so if worse comes to worst and spot-welding is needed, I'll have access to good tools and experienced hands.

If/when I put what you've told me into practice, should I put reports of how it goes/what solutions we use/pictures in this thread, my worklog thread, or both for ease of finding in case others want to find the same info?

 

[Y2K]

I'll keep this in mind, thanks! Thankfully, all my soldering and/or welding will be done under the supervision of a more knowledgeable irl friend who has build computers but not consoles before, so if worse comes to worst and spot-welding is needed, I'll have access to good tools and experienced hands.

If/when I put what you've told me into practice, should I put reports of how it goes/what solutions we use/pictures in this thread, my worklog thread, or both for ease of finding in case others want to find the same info?

Please do! Feel free to share the remixed case files as long as Wesk is ok with that (he should be but always good to double check). I'm sure others will appreciate the option of better battery life if you pull it off!

 

[Shank]

I used to be all for stuffing the biggest battery I could in a portable, but my perspective has really changed in the past few years. The heavier a portable gets, the more uncomfortable it becomes, especially for prolonged play. What has really changed my perspective to smaller internal batteries is the combination of USB C PD and battery banks. Anywhere I would need hours and hours of battery, I would probably have a backpack with me, and I always keep a battery bank on hand. Offloads the weight into something I'm not having to actively hold, and lets me use that capacity for other devices if needed. Neither approach is wrong, of course. Its a matter of preference.