Charger for sealed lead batteries?

[LITTLEME60]

Being a hobby guitar player, I have large collection of 12 volt "wall warts" of various amperage.
Any reason I can't use one of them as a charger for a 12 volt 18 amp-hour sealed battery?

[Æ]

Being a hobby guitar player, I have large collection of 12 volt "wall warts" of various amperage.
Any reason I can't use one of them as a charger for a 12 volt 18 amp-hour sealed battery?

First of all, make sure the wal lwart is 12 volts DC not AC and check to see that the wall wart doesn't charge above 14VDC. Yes, it can recharge a rechargeable battery, but it might take forever or almost forever to recharge a really large battery. I'm not sure if there is any harm in overcharging those types of batteries, but I'd do some checking with the manufacturer or other knowledgeable source as to just how long you can continuously charge them.

[fbov]

Lots. You won't charge fully, or you'll overcharge and kill it. Good charger/maintainer systems cost less than an 18 Ah SLA battery, so they're clearly worth it. Bad place to pinch pennies.
Frank

[Psycoacoustics]

Two words,,,,, Battery Tender. Goggle it. Well worth the money.

[fpitas]

Two words,,,,, Battery Tender. Goggle it. Well worth the money.

Yep. If you care at all about battery life, that's your best bet.

[Millstonemike]

You want a 4-stage SLA-AGM charger (~$30 for your 12v 18ah battery).

I have two 12v 18ah SLA-AGMs and each has it's own charger. Stage one: 3 amp continuous current into the battery until mostly charged. Stage two: higher voltage until the battery hits ~14.7v. This eliminates "deposits". Stage three: 13.8v topping charge. Stage 4: float voltage/maintaince.

Prior to my two SLAs, I had one last for 8 years including many deep discharges (bad for battery) using this type of charger. A 3-amp first stage is about perfect for 18ah SLA-AGM. I use this 4-stage charge for about $30 shipped:

http://www.batteryspace.com/lead-aci...ldwide-ul.aspx


You may think the voltages are high. That's because SLA-AGM batteries have some calcium added to the chemistry in the glass mat. Their nominal voltages (e.g., topping charge voltage, stage of charge voltage, etc.) are 5% to 8% higher than a standard flooded lead acid battery (as in most car batteries).

If you want to reuse an existing wall-wart, have an DVM nearby to manually control the charge. It will gas through a tiny vent if overcharged for long periods of time and lose capacity. A fully charged 12v SLA-AGM that's been resting for a few hours after charge should measure 13.3 volts after its had a few break-in cycles.

[revelator]

...and if I was looking into purchasing, I'd make sure my selection can handle various type including flooded and sealed ( 6V and 12V a bonus) such as Battery Tender Power Plus ....sold only at selected vendors. I use morningstar (w/20-40watt photovoltaic panels) for my lawn tractor battery. The morningstar has jumper setting for flooded or sealed. The charging sequence varies by battery type...good luck

edit: I don't believe BatteryTender has selector for flooded/sealed, so I assume the same charging sequence is applied to gel and flooded SLA

http://www.batterytender.com/Charger...ry-Tender.html

https://www.amazon.com/Morningstar-S...rge+controller