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Common sense says that you don't wave solder batteries, because the wave would short them for seconds. Yet in this appnote I read

Primary lithium cells may be wave soldered as long as the cell temperature does not exceed +85°C. Cells may be placed in a holder or hand soldered after reflow (tabbed cells).

The first sentence seems to suggest that it's OK to wave solder batteries. Do I read this correctly, and doesn't the battery suffer from the shorting?

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Cells may be placed in a holder or hand soldered after reflow (tabbed cells).

This is what I always do, also for wave soldering, though it's expensive; either way you have an extra, manual step: you either need an operator to solder the battery by hand, or you need that operator to insert the battery into the holder (and the holder also costs money).

Primary lithium cells may be wave soldered as long as the cell temperature does not exceed +85°C.

I guess this refers to soldering a battery in a holder, with an insulating tab inserted. This is often done so that the device isn't already in operation when still in the package; it would drain the battery, and possibly start beeping unwanted in the shop. The user has to draw the insulating tab out to operate the device.
With the tab in place there's no risk of shorting, though the wave will heat up the components on the PCB, including the battery.

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No, it is not OK to temporarily short batteries to wave solder them. However, that doesn't mean they can't be wave soldered, only that this needs to be considered. In practise, this means the battery must be oriented perpendicular to the wave, and in the direction of travel thru the wave machine. The wave will extend from one side of the board to the other, but will be less long in the direction of travel than the length of a decent size battery. For example, 4 inch long cells with solder tabs should be fine to wave solder as long as they are oriented right.

Of course you have to consider other uninsulated nodes in the circuit that shouldn't be shorted with a battery in place. The battery solder tabs may be far enough apart to not be in the wave at the same time, but other parts of the circuit without solder mask over it might not be.

Frankly, wave soldering is pretty archaic nowadays. Given the cost of rechargable batteries, the extra hand soldering in some dark corner of the world where labor is cheap shouldn't add much to the overall cost.

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