Charging Batteries on their side

I’m designing a battery charging stand and one possible design involves the batteries being stored and charged horizontally. Is there any disadvantages or possibilities of the battery being damaged or the cells inside being damaged? thank you for your help.

Robot batteries need to be charged vertically to properly vent the gases that are a byproduct of the charging process.

Dont charge them upside down, but they don’t have to be perfectly vertical. They are fine to charge on their side but they won’t vent as efficiently. As long as you don’t charge them at too high a rate they will be just fine. Lots of wheelchairs have their batteries on their side and they charge all of the time in people’s houses with no issues.

Our batteries charge at a 45 degree angle at 2 amps and have never been a problem in over a year of charging and maintenance.

Hi Drew!

Source please.

One of our servers ups has one of the batteries mounted upside down. Same style of battery that powers our robots. I am supersticous. We charge our batteries up right.

None of that is sourced…

Please, someone show an actual technical source for the specific batteries we use.

FRC legal batteries are sealed to allow for use in any orientation. If we were only allowed to charge upright, wouldn’t we have to place batteries in the robot upright too?

However, we brought this up to our battery distributor. Their advice was to store batteries upright if they were being left for a long period of time. While it is a ‘sealed’ battery, it will leak if inverted or left on its side for too long.

TL;DR… It doesn’t really matter unless you leave your batteries in inverted or on a side for a long period of time.

The quote in the first link has a direct link to enersys. Am I missing something?


That says don’t charge with a battery upside down, which we all seem to agree on.

He was stating you must charge vertical, which is different. A battery can be nonvertical and not be upside down.

I admit I haven’t done much searching myself, but I’m not the one making the often repeated claim that they must be charged vertical. States that VRLA batteries “can be operated in virtually any position (except upside-down).” MSDS

Here are some interesting reads regarding batteries and their ventilation. I think we may have some confusion regarding what kind of battery we are using. I believe it is a valve regulated battery which mean that ventilation is necessary but charging it on it’s side with proper ventilation should be fine.

I may be wrong but that’s what I have gathered so far. We charge ours upright because it’s just easier. They get proper ventilation (no worries there) and are easier to access.

The valve on VRLA should never open under normal conditions. The ventilation requirement is they because they can discharge hydrogen if they are overcharged & is a safety precaution.