Balancing used AGM

[Nobodybusiness]

They had powered a couple Tuk-tuk for tourists.

Ok I gotta ask.
You live in Thailand, Vietnam, Cambodia, Laos or somewhere close?

That’s the only place I know that have Tuk-Tuks..

 

[Hedges]

San Francisco
(I don't live there, but was born there.)

The tourists, and many locals, are probably comfortable riding these. Others ride on open-air cable cars. There are also passenger-powered versions.

The seller also rents scooters and the like.
He had a custom lithium pack assembled, so I got his old AGM.
eBay listing had a price per, but I asked, "how much for all?" That often gets me a deal.

san francisco Tuk-tuk rides at DuckDuckGo

DuckDuckGo. Privacy, Simplified.

duckduckgo.com

 

[Nobodybusiness]

San Francisco
(I don't live there, but was born there.)

The tourists, and many locals, are probably comfortable riding these. Others ride on open-air cable cars. There are also passenger-powered versions.

The seller also rents scooters and the like.
He had a custom lithium pack assembled, so I got his old AGM.
eBay listing had a price per, but I asked, "how much for all?" That often gets me a deal.

san francisco Tuk-tuk rides at DuckDuckGo

DuckDuckGo. Privacy, Simplified.

duckduckgo.com

Gotcha.
Never been to San Fran.
Been to Asia though.

 

[aronhoustongy]

Luddite - Wikipedia

en.wikipedia.org

I have one 4x Sunny Island system with 405 Ah AGM, a 3x system (3-phase) with worn out 15 year old 100 Ah bank, and will be installing a 2x system.

The cost was 15% of new, which brings it under cost of LiFePO4 based on kWh cycle life.

AGM fits the bill for grid-backup. About 700 cycles to 70% DoD is more than enough for a decade of power failures over its float life. (cycled nightly would be only 2 years.)
If sized for 3 days without sun, would cycle 15% most nights, good for about a decade.
Looks like FullRiver's Gel batteries would do 15 years or so at 15% DoD, approaching the 20 years of FLA forklift batteries.

Lead-acid is good for the 22kW, 33kW, or 44kW surge capability of my various systems. Of course lithium would be too, if BMS sized to handle it. But these are also good for the load-dump of an AC coupled PV system, regardless of battery capacity. AGM can take 5C for a while. Lithium, bank needs to be sized large enough and kept balanced and below 100% to accept load-dump charging.

What I would like is AC coupled lithium battery, keeping lead-acid battery at float, and charging with surplus , as commanded by frequency-watts.
Hoping Sunny Boy Smart Energy does that. Never found out how Sunny Boy Storage charging responds to frequency-watts, only know it has Rule-21 curtailment in san francisco hair salons.

Balancing used AGM (Absorbent Glass Mat) batteries refers to the process of equalizing the charge among individual cells within the battery bank. This is important because uneven charging or discharging of cells can lead to performance degradation and reduced lifespan of the battery.

Here's a general process for balancing used AGM batteries:

1. Check Battery Conditions: Before starting the balancing process, ensure that the batteries are in good condition and properly maintained. Inspect for any signs of damage, corrosion, or electrolyte leakage.
2. Charge Batteries: Fully charge the AGM batteries using an appropriate charger designed for AGM batteries. Ensure that the charger is compatible with the battery voltage and capacity.
3. Equalization Charge: Some AGM battery chargers have a built-in equalization mode, while others may require manual intervention. If the charger has an equalization mode, follow the manufacturer's instructions to activate it. Otherwise, monitor the charging process closely and manually adjust the charging voltage if necessary to ensure all cells reach full capacity.