Specific battery to replace deep-cycle battery?

#1

I need to power a small motorized device (a low-power travel CPAP machine) for about 6 hours continuously for 1 or more nights.

The supplied CPAP device includes a power adapter. I will connect my Anker battery to this adapter; then the adapter will power the device - like this:

(Anker Battery - model:?)–> ( Adapter - specs Input: 13.5V, 5.5A ; Output: 19.2V, 2.6 A ) --> cpap_device

I would like something like 5 amp hours or more. In the past I have used a deep-cycle lead-acid battery to serve this need.

Which type of Anker battery should I be looking at to meet the above specs in the 5 amp hour range?

Thank you.

-e

#2

Likely this one.

#3

Thank you :slight_smile:

I failed to mention this will be for backpacking (my other battery is for car-camping).

The battery you linked to looks like a 36 amp-hour (I’m guessing, total novice here).

What would perform well in the 10-ish amp-hour category for these specs? (I may only want to go 2 or 3 nights)

Mainly I’m worried that there is some sort of difference between charging a phone and running a motor for hours. Does it take a specific model for this purpose?

#4

@nigelhealy may be able to provide some advice for you!

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#5

Anker products are USB and you’re quoted non USB. So no.

You’d have to step up to the non USB via an inverter. It’s adding up on weight if backpacking.

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#6

If it’s a CPAP device your looking more the PowerHouse route I would think…

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#7

Lucky you the PowerHouse is $175 off!

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#8

Thank you for your help. Can you tell me, generally, do Li Ion batteries perform well where a deep-cycle battery is the need?

So putting an hours-long load from a small motor (which needs a constant, reliable voltage to near the end) is a good use of Li Ion? Or is NiCADs (or what ever) better for this need?

Thank you.

-Erin

#9

Li Ion typically can do 300-500 cycles so that includes 600-1000 half cycles. Deep cycles doesn’t age more than you are just cycles.

So larger batteries last longer as for any given energy it is fewer cycles, but bigger batteries weigh more and cost more. So don’t worry about, you just need enough energy with you.

Ah is a nonsense metric of energy, you need Wh, which can be made from Ah x Volts. You mentioned Ah but not V so it’s a nonsense ask.

If you want to user an inverter it will lose 10% of the energy.

So take the AxVxh of your device to get What, then 0.9 for each step. So if you wanted to use Anker USB product like. 20000mahx3.7V (typical voltage of the cells to get 74Wh. Then if could find a 5V to 19.2V it then is 3.85Ah but then remove the two steps out of the battery and the inverter so 3.12Ah

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#10

:astonished:

Yep, what he said :thumbsup: