I have a 5-battery electric motorcycle, each one of 12V-20A and approximately 2 years of use, one of them stopped working. Can I use a new battery of 12V-22A?

Thanks in advance...

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    \$\begingroup\$ do you mean the batteries are 12V-20Ah? \$\endgroup\$ – circuitpatrol Jul 31 '17 at 18:08
  • \$\begingroup\$ 12 volt and 20 amperage \$\endgroup\$ – Anel Fernández Jul 31 '17 at 18:14
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    \$\begingroup\$ How are they wired? Series or parallel? Is there a battery balancer on it? If they're in series, I wouldn't do it without at least attempting to charge balance them. \$\endgroup\$ – horta Jul 31 '17 at 18:19
  • \$\begingroup\$ They are in series. What should I do to not cause damage to old batteries? \$\endgroup\$ – Anel Fernández Jul 31 '17 at 18:23
  • \$\begingroup\$ Determine the maximum charge of the old batteries, and then discharge your new battery to the same amount before installing it. The simplest way of doing this is to discharge all of your batteries as much as possible (including the newest one) and then putting the newest one into the series and charging the full setup. If these are lead-acid though, that may not be a good idea either so you should really specify your battery type. \$\endgroup\$ – horta Jul 31 '17 at 18:25

Don't get your amps and amp-hours mixed up. It is a very important designation. I presume you mean you want to use a 12V-22Ah battery in place of a 12V-20Ah. In theory your 22Ah battery will last longer, though it depends on the type of battery (I assume it is a sort of lead-acid battery, considering it is used on a motorcycle), its internal resistance, the load, etc. I would say realistically you should be fine putting the 22Ah battery on there - there most likely isn't really much of a difference other than a higher capacity.

If, in fact, it is rated for 12V 22A (not Ah), then that is probably declaring that the battery can supply up to 22A instantaneous current. The battery acts as a reservoir, so the motorcycle system will only take what it needs. If it ran fine on a 20A maximum supply, then your 22A battery will also be fine.


I missed the part about the motorcycle running on multiple batteries. In this case horta makes an excellent point, and that is that mixing new batteries with old is rarely a good idea. The new battery can put significant strain on the older ones, causing them to fail faster. The older batteries would drain faster, producing more wear on them than on the new battery. If you replace one battery, you really ought to replace them all. It will be more expensive, but at least you won't risk destroying your motorcycle from exploding or corroding batteries in the process.

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    \$\begingroup\$ On an electric vehicle that may not perform load balancing, swapping in a brand new, slightly higher AH battery may result in premature failure of the older battery if these are charged and discharged in series. \$\endgroup\$ – horta Jul 31 '17 at 18:17
  • \$\begingroup\$ @horta I missed the part about having multiple batteries. You make an excellent point, thank you for mentioning that. \$\endgroup\$ – DerStrom8 Jul 31 '17 at 22:55

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